Fix logConfig field in Compute Health Check resource.

[upodroid]

Fixes: hashicorp/terraform-provider-google#7016

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Release Note Template for Downstream PRs (will be copied)

compute: set the default value for log_config.enable on `google_compute_health_check` to avoid permanent diff on plan/apply. 

[modular-magician]

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[modular-magician]

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

Diff report:

Terraform Beta: Diff ( 1 file changed, 1 insertion(+))

[upodroid]

@ndmckinley Can i get this merged? It is causing me issues.

 REDACTED  MCW0CDP3YY  ~  go  …  github.com  hashicorp  terraform-provider-google-beta   master  37⬇  8✎  USAGE  $    make testacc TEST=./google-beta TESTARGS='-run=TestAccComputeHealthCheck_healthCheckWithLoggingExample'
==> Checking source code against gofmt...
==> Checking that code complies with gofmt requirements...
TF_ACC=1 TF_SCHEMA_PANIC_ON_ERROR=1 go test ./google-beta -v -run=TestAccComputeHealthCheck_healthCheckWithLoggingExample -timeout 240m -ldflags="-X=github.com/hashicorp/terraform-provider-google-beta/version.ProviderVersion=acc"
=== RUN   TestAccComputeHealthCheck_healthCheckWithLoggingExample
=== PAUSE TestAccComputeHealthCheck_healthCheckWithLoggingExample
=== CONT  TestAccComputeHealthCheck_healthCheckWithLoggingExample
--- PASS: TestAccComputeHealthCheck_healthCheckWithLoggingExample (26.45s)
PASS
ok      github.com/hashicorp/terraform-provider-google-beta/google-beta 28.693s