Upgrade cabal to 3.14.x

[Cmdv]

CI's are currently breaking on 3.14+ so we need to upgrade and change version in nix flake

[sgillespie]

As it turns out, it's a bit more complicated than making it build with the Cabal 3.14 library. There's another issue in cabal-install, that prevents our tests from running:

Test suite schema-rollback: RUNNING...                                                                                                
Git Revision: 6aefd2574bca9175a9fe71d01a044d29f9d0d173                                                                                
Running in directory: /home/sgillespie/dev/iohk/                                                                                      
schema-rollback: cardano-db/src/Cardano/Db/Schema/BaseSchema.hs: withBinaryFile: does not exist (No such file or directory)