chore(deps): update actions/cache action to v4

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
actions/cache	action	major	v3 -> v4

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Release Notes

actions/cache (actions/cache)

v4

Compare Source

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Configuration

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[nodebb-misty]

💡 Friendly Note

This pull request was made against the develop branch, which is reserved for commits destined for a minor or major release.If your commits simply fixes a bug, please rebase this PR against the master instead.

• patch releases — bug fixes only
• minor releases — new features, enhancements, and bug fixes
• major releases — breaking changes, including all of the above

Thanks!