fix module loader cache

[Monti-27]

Fixes #5270.

This makes SimpleModuleLoader cache modules with their import attributes instead of only by path.
It also adds a regression test for the json case where the same path is imported once with attributes and later without them.

Tests:

• cargo test -p boa_engine --test imports -- --nocapture
• cargo test -p boa_engine --test module -- --nocapture
• cargo clippy -p boa_engine --all-features --all-targets -- -D warnings

[github-actions]

Test262 conformance changes

Test result	main count	PR count	difference
Total	52,963	52,963	0
Passed	50,732	50,732	0
Ignored	1,426	1,426	0
Failed	805	805	0
Panics	0	0	0
Conformance	95.79%	95.79%	0.00%

Tested main commit: f075094f9674f9919b4d2e85ca1bcba410bf34b0
Tested PR commit: bf62774e09d8b3e926b3d09b0d15427c669eaf4f
Compare commits: f075094...bf62774

[codecov]

Codecov Report

❌ Patch coverage is 66.66667% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 59.73%. Comparing base (6ddc2b4) to head (bf62774).
⚠️ Report is 921 commits behind head on main.

Files with missing lines	Patch %	Lines
core/engine/src/module/loader/mod.rs	66.66%	2 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #5278       +/-   ##
===========================================
+ Coverage   47.24%   59.73%   +12.49%     
===========================================
  Files         476      589      +113     
  Lines       46892    63477    +16585     
===========================================
+ Hits        22154    37920    +15766     
- Misses      24738    25557      +819     

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