feat: Added Redis version

[aomegax]

List of changes

• added redis version variable

Motivation and context

• version 4 is retiring

Type of changes

• [ ] Add new module
• [x] Update existing module
• [ ] Remove existing module

Does this introduce a breaking change?

• [ ] Yes
• [x] No

Other information

Run checks

Useful commands to run checks on local machine

bash .utils/terraform_run_all.sh init local
pre-commit run -a

[andrea-putzu]

@aomegax è possibile fare il merge?

[github-actions[bot]]

:tada: This PR is included in version 4.15.0 :tada:

The release is available on GitHub release

Your semantic-release bot :package::rocket: