feat: Add identifier output

[daroga0002]

Description

It solves #495

Motivation and Context

Because changes in terraform provider v5
exactly:

resource/aws_db_instance: id is no longer the AWS database identifier - id is now the dbi-resource-id. Refer to identifier instead of id to use the database's identifier 

there is problem with setting a replicated RDS because db_instance_id is returning dbi-resource-id and replicate_source_db require identifier of database.

Breaking Changes

No it is adding a output which is available very long in terraform provider v2, v3 and v4

How Has This Been Tested?

• I have updated at least one of the examples/* to demonstrate and validate my change(s)
• I have tested and validated these changes using one or more of the provided examples/* projects

• I have executed pre-commit run -a on my pull request

[daroga0002]

CI is failing because issue with vpc module. I have created #497 to solve this

[antonbabenko]

This issue has been resolved in version 6.0.0 🎉

[github-actions]

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