[Fix] Use cluster list API to determine pinned cluster status

[bgrams]

Changes

Modify setPinnedStatus to use the clusters list API internally for determining the pinning status of a cluster. The existing implementation using the cluster events API subjects the resource to drift as events expire after a period of time.

Closes #3616

Tests

• Coverage added to TestResourceClusterCreate and TestResourceClusterCreatePinned.

• Fixtures modified to mock the necessary API calls in all other relevant tests.

• TestAccClusterResource_PinAndUnpin acceptance test added

• [x] make test run locally

• [ ] relevant change in docs/ folder

• [x] covered with integration tests in internal/acceptance

• [x] relevant acceptance tests are passing

• [x] using Go SDK

[github-actions[bot]]

If integration tests don't run automatically, an authorized user can run them manually by following the instructions below:

Trigger: go/deco-tests-run/terraform

Inputs:

• PR number: 4203
• Commit SHA: 1011fee8905808035dab7aabb0db58c960fdb0e2

Checks will be approved automatically on success.

[alexott]

@bgrams I'm really thinking if we even need to use any additional APIs. I now see that pinned clusters have the non-emptypinned_by_user_name field. I need to clarify with the clusters team if it's enough...

[bgrams]

Oh, that would be convenient. I don't see this field in the API docs or CLI output. Lmk and I can adapt this PR if needed.

[bgrams]

Thanks! Will these run automatically or is manual action required?

[alexott]

I'll run them when we fix one of the environments where tests are currently failing

[eng-dev-ecosystem-bot]

Test Details: go/deco-tests/11793935188