Fix grpc healthcheck behaviour.

[rileykarson]

Make up for the fact that past!Riley did not run the tests for #3825

Followup for hashicorp/terraform-provider-google#6826

If this PR is for Terraform, I acknowledge that I have:

• Searched through the issue tracker for an open issue that this either resolves or contributes to, commented on it to claim it, and written "fixes {url}" or "part of {url}" in this PR description. If there were no relevant open issues, I opened one and commented that I would like to work on it (not necessary for very small changes).
• Generated Terraform, and ran make test and make lint to ensure it passes unit and linter tests.
• Ensured that all new fields I added that can be set by a user appear in at least one example (for generated resources) or third_party test (for handwritten resources or update tests).
• Ran relevant acceptance tests (If the acceptance tests do not yet pass or you are unable to run them, please let your reviewer know).
• Read the Release Notes Guide before writing my release note below.

Release Note Template for Downstream PRs (will be copied)

bug fix for an unreleased field

[modular-magician]

Hi! I'm the modular magician. Your PR generated some diffs in downstreams - here they are.

Diff report:

Terraform GA: Diff ( 4 files changed, 32 insertions(+), 2 deletions(-))
Terraform Beta: Diff ( 4 files changed, 32 insertions(+), 2 deletions(-))
TF Conversion: Diff ( 2 files changed, 30 insertions(+))

[modular-magician]

I have triggered VCR tests based on this PR's diffs. See the results here: "https://ci-oss.hashicorp.engineering/viewQueued.html?itemId=140696"

[modular-magician]

I have triggered VCR tests in RECORDING mode for the following tests that failed during VCR: TestAccDataSourceGoogleBigqueryDefaultServiceAccount_basic|TestAccDataSourceDNSKeys_basic|TestAccDataSourceDnsManagedZone_basic|TestAccDataSourceDNSKeys_noDnsSec|TestAccDataSourceComputeNetworkEndpointGroup|TestAccDataSourceComputeImage|TestAccDataSourceGoogleComputeDefaultServiceAccount_basic|TestAccDataSourceGoogleComputeInstanceGroup_basic|TestAccDataSourceGoogleComputeInstanceGroup_fromIGM|TestAccDataSourceGoogleComputeInstanceGroup_withNamedPort|TestAccDataSourceGoogleCloudFunctionsFunction_basic|TestAccDataSourceComputeAddress|TestAccDataSourceComputeBackendBucket_basic|TestAccDataSourceComputeBackendService_basic|TestAccDataSourceComputeGlobalAddress|TestAccDataSourceGoogleForwardingRule|TestAccDataSourceComputeNodeTypes_basic|TestAccComputeRegions_basic|TestAccComputeZones_basic|TestAccDataSourceComputeInstanceSerialPort_basic|TestAccDataSourceGoogleNetwork|TestAccDataSourceComputeInstance_basic|TestAccDataSourceComputeResourcePolicy|TestAccDataSourceComputeRouter|TestAccDataSourceGoogleSubnetwork|TestAccDataSourceComputeSslCertificate|TestAccDataSourceGoogleSslPolicy|TestAccDataSourceGoogleVpnGateway|TestAccContainerClusterDatasource_zonal|TestAccContainerClusterDatasource_regional|TestAccDataSourceGoogleStorageProjectServiceAccount_basic|TestAccBigQueryTableIamBindingGenerated|TestAccBigQueryTableIamMemberGenerated|TestAccBigQueryTableIamPolicyGenerated|TestAccBigQueryTableIamBindingGenerated_withCondition|TestAccBigQueryTableIamMemberGenerated_withCondition|TestAccBigQueryTableIamPolicyGenerated_withCondition|TestAccCloudFunctionsCloudFunctionIamBindingGenerated|TestAccCloudFunctionsCloudFunctionIamMemberGenerated|TestAccCloudFunctionsCloudFunctionIamPolicyGenerated|TestAccComputeInstanceIamBindingGenerated|TestAccComputeInstanceIamMemberGenerated|TestAccComputeInstanceIamBindingGenerated_withCondition|TestAccComputeInstanceIamMemberGenerated_withCondition|TestAccComputeInstanceIamPolicyGenerated|TestAccComputeSubnetworkIamMemberGenerated|TestAccComputeSubnetworkIamBindingGenerated|TestAccComputeInstanceIamPolicyGenerated_withCondition|TestAccComputeSubnetworkIamBindingGenerated_withCondition|TestAccComputeSubnetworkIamPolicyGenerated|TestAccComputeSubnetworkIamMemberGenerated_withCondition|TestAccComputeSubnetworkIamPolicyGenerated_withCondition|TestAccIapAppEngineVersionIamBindingGenerated|TestAccIapAppEngineVersionIamMemberGenerated|TestAccIapAppEngineVersionIamBindingGenerated_withCondition|TestAccIapAppEngineVersionIamPolicyGenerated|TestAccIapAppEngineVersionIamMemberGenerated_withCondition|TestAccIapTunnelInstanceIamBindingGenerated|TestAccIapTunnelInstanceIamMemberGenerated|TestAccIapAppEngineVersionIamPolicyGenerated_withCondition|TestAccIapTunnelInstanceIamBindingGenerated_withCondition|TestAccIapTunnelInstanceIamMemberGenerated_withCondition|TestAccIapTunnelInstanceIamPolicyGenerated|TestAccIapWebBackendServiceIamBindingGenerated|TestAccIapTunnelInstanceIamPolicyGenerated_withCondition|TestAccIapWebBackendServiceIamMemberGenerated|TestAccIapWebBackendServiceIamBindingGenerated_withCondition|TestAccIapWebBackendServiceIamMemberGenerated_withCondition|TestAccIapWebBackendServiceIamPolicyGenerated|TestAccIapWebBackendServiceIamPolicyGenerated_withCondition|TestAccIapAppEngineServiceIamBindingGenerated|TestAccIapAppEngineServiceIamMemberGenerated|TestAccIapAppEngineServiceIamPolicyGenerated|TestAccIapAppEngineServiceIamMemberGenerated_withCondition|TestAccIapAppEngineServiceIamBindingGenerated_withCondition|TestAccIapAppEngineServiceIamPolicyGenerated_withCondition|TestAccStorageBucketIamBindingGenerated|TestAccStorageBucketIamMemberGenerated|TestAccStorageBucketIamBindingGenerated_withCondition|TestAccStorageBucketIamMemberGenerated_withCondition|TestAccActiveDirectoryDomain_activeDirectoryDomainBasicExample|TestAccAppEngineApplicationUrlDispatchRules_appEngineApplicationUrlDispatchRulesBasicExample|TestAccAppEngineServiceSplitTraffic_appEngineServiceSplitTrafficExample|TestAccAppEngineStandardAppVersion_appEngineStandardAppVersionExample|TestAccBigQueryDataset_basic|TestAccBigQueryDataset_bigqueryDatasetBasicExample|TestAccBigQueryDataset_datasetWithContents|TestAccBigQueryDataset_access|TestAccBigQueryDataset_regionalLocation|TestAccBigQueryJob_bigqueryJobQueryExample|TestAccBigQueryJob_bigqueryJobQueryTableReferenceExample|TestAccBigQueryJob_bigqueryJobLoadExample|TestAccBigQueryJob_bigqueryJobLoadTableReferenceExample|TestAccBigQueryJob_bigqueryJobExtractExample|TestAccBigQueryJob_bigqueryJobExtractTableReferenceExample|TestAccBigQueryDatasetAccess_view|TestAccBigQueryDatasetAccess_iamMember|TestAccBigQueryDatasetAccess_basic|TestAccBigQueryDatasetAccess_allUsers|TestAccBigQueryDatasetAccess_allAuthenticatedUsers You can view the result here: "https://ci-oss.hashicorp.engineering/viewQueued.html?itemId=140699"

[upodroid]

😄 i'm getting better with newer PRs that i'm submitting.

[rileykarson]

@upodroid All good! I assumed I'd confirmed the tests when I LGTMed in the first place.