feat: Use unique name for the spark job execution IRSA policy

[alanty]

What does this PR do?

Create a unique name for the spark job execution IRSA policy by using name_prefix instead of name.
solves #668

Motivation

If you deploy the solution with the same name and account but different regions, the name of this policy conflicts and blocks the creation.

More

• Yes, I have tested the PR using my local account setup (Provide any test evidence report under Additional Notes)
• Mandatory for new blueprints. Yes, I have added a example to support my blueprint PR
• Mandatory for new blueprints. Yes, I have updated the website/docs or website/blog section for this feature
• Yes, I ran pre-commit run -a with this PR. Link for installing pre-commit locally

For Moderators

• E2E Test successfully complete before merge?

Additional Notes

this could just as easily be avoided by not using the same name in the variables for the solution.