python3Packages.asyncpg: fix hash

The hash to the patch is broken, even with the original revision
which adds asyncpg (ee2161c5). As the
downloaded patch seems fine, I guess that it was generated with
`nix-prefetch-url` (the hashes for `fetchpatch` usually differ) and the
issue wasn't found as the fixed-output-derivation was already in the
contributor's store.

See https://hydra.nixos.org/build/102495795

ZHF #68361