build: Update actions/cache action to v4

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
actions/cache	action	major	v2 -> v4

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Release Notes

actions/cache (actions/cache)

v4

Compare Source

v3

Compare Source

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Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (1639d0c) 100.00% compared to head (0380999) 100.00%.

Additional details and impacted files

@@            Coverage Diff            @@
##              main      #180   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            2         2           
  Lines          100       100           
  Branches        18        18           
=========================================
  Hits           100       100           

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