Break cyclic references when there is an exception handling a request (#10569)
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## What do these changes do?
This is a partial fix for #10548
- There is still another case for `SystemRoute`s that needs to be
addressed. No reproducer available yet.
- There is also another case on the client side on connection refused
that still needs to be addressed
https://github.com/aio-libs/aiohttp/issues/10548#issuecomment-2727643763
## Are there changes in behavior for the user?
fixes memory leak
## Is it a substantial burden for the maintainers to support this?
no
(cherry picked from commit dfbf782ba4ea3eabfe052e6224727cf83efdffb5)