release/3.x: Backport #25768; Remove Computed from apply_immediately

[ewbankkit]

Description

Backports #25768 to release/3.x.

Relations

Relates #25711.

Output from Acceptance Testing

% make testacc TESTARGS='-run=TestAccRDSInstance_basic\|TestAccRDSInstance_identifierGenerated\|TestAccRDSInstance_subnetGroup' PKG=rds ACCTEST_PARALLELISM=3
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go test ./internal/service/rds/... -v -count 1 -parallel 3  -run=TestAccRDSInstance_basic\|TestAccRDSInstance_identifierGenerated\|TestAccRDSInstance_subnetGroup -timeout 180m
=== RUN   TestAccRDSInstance_basic
=== PAUSE TestAccRDSInstance_basic
=== RUN   TestAccRDSInstance_subnetGroup
=== PAUSE TestAccRDSInstance_subnetGroup
=== CONT  TestAccRDSInstance_basic
=== CONT  TestAccRDSInstance_subnetGroup
--- PASS: TestAccRDSInstance_basic (528.91s)
--- PASS: TestAccRDSInstance_subnetGroup (920.11s)
PASS
ok  	github.com/hashicorp/terraform-provider-aws/internal/service/rds	924.101s

[kwilczynski]

@ewbankkit, thank you! 🙇

[github-actions]

This functionality has been released in v3.76.0 of the Terraform AWS Provider. Please see the Terraform documentation on provider versioning or reach out if you need any assistance upgrading.

For further feature requests or bug reports with this functionality, please create a new GitHub issue following the template. Thank you!

[github-actions]

I'm going to lock this pull request because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues.
If you have found a problem that seems related to this change, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.