haskellPackages.taffybar: override src until next Hackage update

[rvl]

Motivation for this change

Taffybar 3.2.5 fixes dyre compatibility, but is not in Hackage as of 2021-05-19T07:17:55Z.

To be merged into #123682.

cc @IvanMalison @cdepillabout

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS linux)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Added a release notes entry if the change is major or breaking
• Fits CONTRIBUTING.md.

[colonelpanic8]

It should be in hackage, maybe I messed up the upload?

[colonelpanic8]

Oh I see it needed to be in the relevant hackage snapshot. Okay, looks good to me!

[cdepillabout]

Looks good, thanks for updating this!

[rvl]

Yeah, I wasn't sure whether to add an override like this or to bump the pinned hackage version and regenerate.
But I think the latter could cause new build errors, and then we would never get the haskell-updates PR merged.