Move the URL class to using the boa_class macro

[hansl]

Instead of the js_class one which was weird to use. This is much cleaner and takes less space.

Please note we cannot move Console, since it is not a class.

[codecov]

Codecov Report

Attention: Patch coverage is 45.45455% with 36 lines in your changes missing coverage. Please review.

Project coverage is 52.40%. Comparing base (6ddc2b4) to head (ea000f6).
Report is 444 commits behind head on main.

Files with missing lines	Patch %	Lines
core/runtime/src/url.rs	45.45%	36 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4294      +/-   ##
==========================================
+ Coverage   47.24%   52.40%   +5.16%     
==========================================
  Files         476      495      +19     
  Lines       46892    51462    +4570     
==========================================
+ Hits        22154    26971    +4817     
+ Misses      24738    24491     -247     

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[HalidOdat]

Looks good to me! Just a question :)