Move ordinary function [[ConstructorKind]] to CodeBlock

[HalidOdat]

Since the [[ConstructorKind]] is known at compile time and it doesn't change, this moves it to CodeBlock in the CodeBlockFlags bitflags.

[github-actions]

Test262 conformance changes

Test result	main count	PR count	difference
Total	95,609	95,609	0
Passed	75,978	75,978	0
Ignored	18,872	18,872	0
Failed	759	759	0
Panics	0	0	0
Conformance	79.47%	79.47%	0.00%

[codecov]

Codecov Report

Attention: 6 lines in your changes are missing coverage. Please review.

Comparison is base (5e89c4e) 45.40% compared to head (67ad875) 45.39%.
Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3439      +/-   ##
==========================================
- Coverage   45.40%   45.39%   -0.02%     
==========================================
  Files         483      483              
  Lines       49790    49787       -3     
==========================================
- Hits        22609    22602       -7     
- Misses      27181    27185       +4     

Files	Coverage Δ
boa_engine/src/builtins/function/mod.rs	38.34% <100.00%> (-1.30%)	⬇️
boa_engine/src/bytecompiler/class.rs	16.33% <100.00%> (+0.63%)	⬆️
boa_engine/src/vm/opcode/push/class/mod.rs	66.66% <ø> (-7.41%)	⬇️
boa_engine/src/vm/code_block.rs	28.16% <75.00%> (+0.54%)	⬆️
boa_engine/src/object/internal_methods/function.rs	91.08% <44.44%> (-0.09%)	⬇️

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