test: add cache testing

[tsctx]

No description provided.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 87.28%. Comparing base (e39a632) to head (fc5398f).
⚠️ Report is 1542 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2623      +/-   ##
==========================================
+ Coverage   85.54%   87.28%   +1.73%     
==========================================
  Files          76       81       +5     
  Lines        6858     7293     +435     
==========================================
+ Hits         5867     6366     +499     
+ Misses        991      927      -64     

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[mcollina]

lgtm

[KhafraDev]

I'm pretty sure Every test here is already covered by WPTs. There is no reason to add these tests.

[tsctx]

@KhafraDev #2612 (comment)

[KhafraDev]

I think Matteo meant was that a test specifically for accessing the signal was needed, not that we need to duplicate the tests