[SREP-1313] feat : Update isolation workflow to enforce policy Arn from backplane-api assume-role-sequence endpoint

What type of PR is this?

• fix (Bug Fix)
• feat (New Feature)
• docs (Documentation)
• test (Test Coverage)
• chore (Clean Up / Maintenance Tasks)
• other (Anything that doesn't fit the above)

What this PR does / Why we need it?

Enforce the session policy Arn to the Customer AWS account on assume role chain

Which Jira/Github issue(s) does this PR fix?

https://issues.redhat.com/browse/SREP-1313

• Related Issue #
• Closes #

Special notes for your reviewer

Unit Test Coverage

Guidelines

• If it's a new sub-command or new function to an existing sub-command, please cover at least 50% of the code
• If it's a bug fix for an existing sub-command, please cover 70% of the code

Test coverage checks

• Added unit tests
• Created jira card to add unit test
• This PR may not need unit tests

Pre-checks (if applicable)

• Ran unit tests locally
• Validated the changes in a cluster
• Included documentation changes with PR
• Backward compatible

/label tide/merge-method-squash