chore(ci): tidy up actions

[BethGriggs]

Description of the change

Updated to use new GH Actions env syntax. No impact on Chart.

Existing or Associated Issue(s)

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
No data about Coverage
No data about Duplication

See analysis details on SonarCloud

[BethGriggs]

Would anyone mind reviewing this one? (perhaps cc: @coreydaley?)

[nickboldt]

sure, looks OK.