make the location field required in google_storage_bucket

[shuyama1]

fixes hashicorp/terraform-provider-google#4422

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)

storage: changed the `location` field to `Required` in `google_storage_bucket ` resource

[modular-magician]

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

Diff report:

Terraform GA: Diff ( 71 files changed, 400 insertions(+), 214 deletions(-))
Terraform Beta: Diff ( 73 files changed, 433 insertions(+), 231 deletions(-))
TF OiCS: Diff ( 11 files changed, 27 insertions(+), 19 deletions(-))

[modular-magician]

I have triggered VCR tests in RECORDING mode for the following tests that failed during VCR: TestAccComputeForwardingRule_update|TestAccContainerNodePool_withGPU|TestAccSqlUser_postgresIAM You can view the result here: https://ci-oss.hashicorp.engineering/viewQueued.html?itemId=211603

[modular-magician]

Tests failed during RECORDING mode: TestAccSqlUser_postgresIAM Please fix these to complete your PR

[rileykarson]

Can you add an entry to the upgrade guide to describe the change? https://github.com/GoogleCloudPlatform/magic-modules/blob/master/mmv1/third_party/terraform/website/docs/guides/version_4_upgrade.html.markdown

[rileykarson]

Wait- I can't read, apparently, missed it while scrolling through the files.

That's a ton of changes to the tests, thanks!

[modular-magician]

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

Diff report:

Terraform GA: Diff ( 71 files changed, 394 insertions(+), 212 deletions(-))
Terraform Beta: Diff ( 73 files changed, 429 insertions(+), 230 deletions(-))
TF OiCS: Diff ( 11 files changed, 27 insertions(+), 19 deletions(-))