ci: caching pip downloads in workflows

[aclfe]

Issue #2944 mentioned five workflows to enable pip caching

• No CHANGELOG update needed

[gemini-code-assist]

Note

Gemini is unable to generate a review for this pull request due to the file types involved not being currently supported.

[github-actions]

Please add bug fixes, new features, breaking changes and anything else you think is worthwhile mentioning to the master (unreleased) section of CHANGELOG.md. If no CHANGELOG update is needed add the following to the PR description: [x] No CHANGELOG update needed

[google-cla]

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CHANGELOG updated or no update needed, thanks! 😄

[aclfe]

CI is green, waiting approval for 3 workflows. Open to any feedback

[aclfe]

@fariss @mike-hunhoff

[aclfe]

Made all changes

[aclfe]

@fariss

[aclfe]

Replied #2969 (comment)

Happy to move in whatever direction team prefers