ci: Fix the python version used by actions/setup-python

[rm3l]

Description of the change

The previous Python version (3.7) seems to no longer be available.

Existing or Associated Issue(s)

https://github.com/redhat-developer/rhdh-chart/actions/runs/12773187597/job/35604468404?pr=54

Additional Information

Checklist

• Chart version bumped in Chart.yaml according to semver.
• Variables are documented in the values.yaml and added to the README.md. The pre-commit utility can be used to generate the necessary content. Use pre-commit run -a to apply changes.
• JSON Schema template updated and re-generated the raw schema via pre-commit hook.
• List tests pass for Chart using the Chart Testing tool and the ct lint command.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[rm3l]

/cherry-pick release-1.3
/cherry-pick release-1.4

Backports needed to fix the CI failures in these release branches.

[openshift-cherrypick-robot]

@rm3l: new pull request created: #81

In response to this:

/cherry-pick release-1.3
/cherry-pick release-1.4

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.

[openshift-cherrypick-robot]

@rm3l: new pull request created: #82

In response to this:

/cherry-pick release-1.3
/cherry-pick release-1.4

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.