fix(fetch): add status 205 to null body status check in Response

[HiteshShonak]

This Pull Request fixes/closes #5207.

It changes the following:

• Add 205 to the is_null_body_status check in response.rs so new Response("x", { status: 205 }) throws a TypeError.
• Update the error message and doc comment to include 205.
• Add a consolidated regression test covering 204, 205, and 304.

Testing:

cargo test -p boa_runtime response -- --nocapture

Spec reference: https://fetch.spec.whatwg.org/#null-body-status

[Copilot]

Pull request overview

This PR updates the Fetch Response implementation to treat HTTP status 205 as a null body status, aligning behavior with the Fetch Standard and fixing #5207.

Changes:

• Add 205 to the is_null_body_status check so new Response("x", { status: 205 }) throws a TypeError.
• Update the related doc comment and error message to include 205.
• Add a regression test that verifies TypeError is thrown for 204, 205, and 304 when a body is provided.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
core/runtime/src/fetch/response.rs	Extends null-body-status detection + updates error message/doc comment to include 205.
core/runtime/src/fetch/tests/response.rs	Adds a consolidated regression test for 204/205/304 body rejection in the constructor.

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[github-actions]

Test262 conformance changes

Test result	main count	PR count	difference
Total	52,963	52,963	0
Passed	50,539	50,539	0
Ignored	1,426	1,426	0
Failed	998	998	0
Panics	2	2	0
Conformance	95.42%	95.42%	0.00%

Tested main commit: 58a24587890677d94618259dfaa5f257ab5ef9c9
Tested PR commit: 4fb5b6e8c3440412fbae91ba1dfa6fdc10a2aadd
Compare commits: 58a2458...4fb5b6e

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 59.82%. Comparing base (6ddc2b4) to head (4fb5b6e).
⚠️ Report is 937 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #5208       +/-   ##
===========================================
+ Coverage   47.24%   59.82%   +12.58%     
===========================================
  Files         476      582      +106     
  Lines       46892    63460    +16568     
===========================================
+ Hits        22154    37967    +15813     
- Misses      24738    25493      +755     

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[jedel1043]

Good catch