Revert "Upgrade python version to 3.12 for all OSs except AL2"

[himani2411]

Description of changes

Reverting PR as we are blocked by the cfn-bootstrap script

• Reverts Upgrade python version to 3.12 for all OSs except AL2 #2869
• Reverts [Test] Fix Python version in kitchen tests related to AWS Batch and CFN Boostrap scripts. In particular, we expect all Oses to use Python 3.12.8, except for AL2 which uses 3.9.20. #2885

This reverts commit 45431e6.

• Describe what you're changing and why you're doing these changes.

Tests

• Describe the automated and/or manual tests executed to validate the patch.
• Describe the added/modified tests.

References

• Link to impacted open issues.
• Link to related PRs in other packages (i.e. cookbook, node).
• Link to documentation useful to understand the changes.

Checklist

• Make sure you are pointing to the right branch.
• If you're creating a patch for a branch other than develop add the branch name as prefix in the PR title (e.g. [release-3.6]).
• Check all commits' messages are clear, describing what and why vs how.
• Make sure to have added unit tests or integration tests to cover the new/modified code.
• Check if documentation is impacted by this change.

Please review the guidelines for contributing and Pull Request Instructions.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.