fix(bench): enable intl_bundled feature for boa_engine

[Lokesh0224]

After #4898, running cargo bench -p boa_benches without --features boa_engine/intl_bundled panics with "Intl is not defined" since the Intl benchmark scripts require the intl feature to be enabled.
This adds intl_bundled as a default feature for boa_benches so cargo bench -p boa_benches works without any panics message: "Intl is not defined".

[github-actions]

Test262 conformance changes

Test result	main count	PR count	difference
Total	52,963	52,963	0
Passed	49,935	49,935	0
Ignored	2,207	2,207	0
Failed	821	821	0
Panics	0	0	0
Conformance	94.28%	94.28%	0.00%

Tested main commit: 1f1cf0301b8a43a5893d535444279b7b11e5b3ce
Tested PR commit: 1be97f6282b2fbdf2f6bb437fe96b437f4385bb8
Compare commits: 1f1cf03...1be97f6

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 59.09%. Comparing base (6ddc2b4) to head (1be97f6).
⚠️ Report is 849 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #5067       +/-   ##
===========================================
+ Coverage   47.24%   59.09%   +11.84%     
===========================================
  Files         476      563       +87     
  Lines       46892    62569    +15677     
===========================================
+ Hits        22154    36974    +14820     
- Misses      24738    25595      +857     

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[jedel1043]

Thanks!