Update all generated resources to 20m timeouts

[rileykarson]

I noticed an OSPolicyAssignment test failed due to timing out, and remembered that the default in Terraform these days was pretty long. I want to say it used to be 2-5 minutes, but it's 20 (or it's possible I misremembered it). I figured it would be easy to align all generated resources to the default or higher, especially given we generally only hit this timeout when GCP drops a request or have badly configured a retry.

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)

provider: changed the default timeout for many resources to 20 minutes, the current Terraform default, where it was less than 20 minutes previously

[modular-magician]

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

Diff report:

Terraform GA: Diff ( 472 files changed, 1271 insertions(+), 1271 deletions(-))
Terraform Beta: Diff ( 500 files changed, 1352 insertions(+), 1352 deletions(-))

[megan07]

LGTM! Thanks!

[modular-magician]

I have triggered VCR tests in RECORDING mode for the following tests that failed during VCR: TestAccDatasourceGoogleServiceNetworkingPeeredDnsDomain_basic|TestAccApigeeEnvironmentIamBindingGenerated|TestAccApigeeEnvironmentIamPolicyGenerated|TestAccCloudbuildWorkerPool_basic|TestAccContainerNodePool_withInvalidUpgradeSettings|TestAccServiceNetworkingPeeredDNSDomain_basic You can view the result here: https://ci-oss.hashicorp.engineering/viewQueued.html?itemId=246755

[modular-magician]

Tests failed during RECORDING mode: TestAccCloudbuildWorkerPool_basic|TestAccContainerNodePool_withInvalidUpgradeSettings Please fix these to complete your PR