fix: replace dynamic secret_manager_config block with static block

[Dutta78]

fix: use static block for secret_manager_config to prevent removal errors

Fixes: #2402

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[apeabody]

/gcbrun

[Dutta78]

Hey @apeabody , let me know if this can be merged

[Dutta78]

Fixed the Merge Conflict. @apeabody please review. thanks.

[apeabody]

/gcbrun

[apeabody]

/gemini review

[apeabody]

• lint / lint (pull_request)

Thanks @Dutta78, from the lint test:

Checking submodule's files generation
diff -r '--exclude=.terraform' '--exclude=.kitchen' '--exclude=.git' /workspace/cluster.tf /tmp/tmp.QdnjomRPbA/workspace/cluster.tf
229a230
> 
237d237
< 
diff -r '--exclude=.terraform' '--exclude=.kitchen' '--exclude=.git' /workspace/modules/beta-autopilot-private-cluster/cluster.tf /tmp/tmp.QdnjomRPbA/workspace/modules/beta-autopilot-private-cluster/cluster.tf
159d158
< 
diff -r '--exclude=.terraform' '--exclude=.kitchen' '--exclude=.git' /workspace/modules/beta-autopilot-public-cluster/cluster.tf /tmp/tmp.QdnjomRPbA/workspace/modules/beta-autopilot-public-cluster/cluster.tf
159d158
< 
diff -r '--exclude=.terraform' '--exclude=.kitchen' '--exclude=.git' /workspace/modules/beta-private-cluster-update-variant/cluster.tf /tmp/tmp.QdnjomRPbA/workspace/modules/beta-private-cluster-update-variant/cluster.tf
252d251
< 
diff -r '--exclude=.terraform' '--exclude=.kitchen' '--exclude=.git' /workspace/modules/private-cluster/cluster.tf /tmp/tmp.QdnjomRPbA/workspace/modules/private-cluster/cluster.tf
239d238
< 
Error: submodule's files generation has not been run, please run the
'make build' command and commit changes

Probably some stray whitespace, 'make build' should fix.

[gemini-code-assist]

Code Review

This pull request consistently replaces dynamic secret_manager_config blocks with static ones across various Terraform files and templates. This change simplifies the configuration logic, making it more straightforward to enable or disable the Secret Manager addon. The corresponding output expressions have also been updated to reflect this simplification, removing unnecessary null and length checks. This is a positive change that improves code clarity and maintainability, and addresses potential issues with dynamic block removal.