ceph: fix cryptography override

Since ba83271 the build fails with

    applying patch /nix/store/46rxbbvl2l3mrxb50y9rzy7ahgx0lraj-d741901dddd731895346636c0d3556c6fa51fbe6.patch
    patching file tests/hazmat/primitives/test_aead.py
    Hunk #1 FAILED at 56.
    Hunk #2 FAILED at 197.
    Hunk #3 FAILED at 378.
    Hunk #4 FAILED at 525.
    Hunk #5 FAILED at 700.
    Hunk #6 FAILED at 844.
    6 out of 6 hunks FAILED -- saving rejects to file tests/hazmat/primitives/test_aead.py.rej

Author: dotlambda

pkgs/tools/filesystems/ceph/default.nix

@@ -195,7 +195,7 @@ let
           hash = "sha256-gFfDTc2QWBWHBCycVH1dYlCsWQMVcRZfOBIau+njtDU=";
         };
 
-        patches = (old.patches or []) ++ [
+        patches = [
           # Fix https://nvd.nist.gov/vuln/detail/CVE-2023-49083 which has no upstream backport.
           # See https://github.com/pyca/cryptography/commit/f09c261ca10a31fe41b1262306db7f8f1da0e48a#diff-f5134bf8f3cf0a5cc8601df55e50697acc866c603a38caff98802bd8e17976c5R1893
           ./python-cryptography-Cherry-pick-fix-for-CVE-2023-49083-on-cryptography-40.patch