Implement FinalizationRegistry

[jedel1043]

Funny GC with its funny semantics

anyways, this implements the last big feature we were missing from the spec. It uses the same pattern from Atomics.waitAsync of (ab)using async jobs to enqueue a cleanup task on a later point in time.

[github-actions]

Test262 conformance changes

Test result	main count	PR count	difference
Total	52,963	52,963	0
Passed	50,070	50,070	0
Ignored	2,072	2,025	-47
Failed	821	868	+47
Panics	0	0	0
Conformance	94.54%	94.54%	0.00%

Tested main commit: 965f38c66d22dbcda4746d9b79c607189530287d
Tested PR commit: bcc2759dab8f6dbadef37a3886801eb8ad192f80
Compare commits: 965f38c...bcc2759

[codecov]

Codecov Report

❌ Patch coverage is 12.66667% with 131 lines in your changes missing coverage. Please review.
✅ Project coverage is 58.97%. Comparing base (6ddc2b4) to head (bcc2759).
⚠️ Report is 857 commits behind head on main.

Files with missing lines	Patch %	Lines
...e/engine/src/builtins/finalization_registry/mod.rs	5.17%	110 Missing ⚠️
...ine/src/object/builtins/jsfinalization_registry.rs	0.00%	12 Missing ⚠️
core/engine/src/job.rs	45.45%	6 Missing ⚠️
core/gc/src/pointers/ephemeron.rs	50.00%	2 Missing ⚠️
core/engine/src/object/jsobject.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #5101       +/-   ##
===========================================
+ Coverage   47.24%   58.97%   +11.72%     
===========================================
  Files         476      565       +89     
  Lines       46892    62816    +15924     
===========================================
+ Hits        22154    37044    +14890     
- Misses      24738    25772     +1034     

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