fix: ac lost on cloned request (#4068)

[gyx1000]

This relates to #4068

Changes

This PR fixes an issue where cloning a Request caused the cloned instance to lose its AbortSignal behavior under certain GC conditions.
The underlying problem was that the signal reference could be garbage-collected prematurely, preventing the abort event from propagating to the cloned request. This resulted in inconsistent abort behavior on the very first request processed after a clone.

The fix ensures the signal and its abort listener remain properly retained across clones, restoring consistent abort propagation for cloned Request objects.

Bug Fixes

• Fixed a bug where Request.clone() or new Request(request), could drop the associated AbortSignal listener during garbage collection.
• Ensured cloned Request objects consistently propagate abort events, including during the initial request lifecycle.

Status

• I have read and agreed to the [Developer's Certificate of Origin][cert]
• Tested
• Benchmarked (optional)
• Documented
• Review ready
• In review
• Merge ready

[KhafraDev]

My comment in the original issue makes it seem like this is not an issue in undici.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.85%. Comparing base (fdafc2a) to head (b3445e4).
⚠️ Report is 7 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4678      +/-   ##
==========================================
- Coverage   92.86%   92.85%   -0.02%     
==========================================
  Files         107      107              
  Lines       33499    33517      +18     
==========================================
+ Hits        31108    31121      +13     
- Misses       2391     2396       +5     

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[tsctx]

My comment in the original issue makes it seem like this is not an issue in undici.

It's undici that is the problem, not node.

Once the parent signal is garbage collected, the child loses its reference and therefore cannot propagate the abort signal, even if the original signal is aborted.