[chore] replace cabal.project.local template and update cabal.project

[MangoIV]

Checklist

• [x] Add a new entry in an appropriate subdirectory of changelog.d
• [x] Read and follow the PR guidelines

[akshaymankar]

package: * applies to all packages not just local pacakges. I think this would fail if protobuf stuff which is not provided by nix has any warnings.

[MangoIV]

can we not overwrite in case we run into warnings for these two packages in future? i.e. package * in general and then package proto-lens-protoc ghc-options -Wwarn?

[MangoIV]

in fact, I deleted my cabal store and am trying to build right now, it doesn't look as though it's problematic.

[MangoIV]

currently proto-lens-protoc and hspec-discover do not emit warnings. I have protected us against them failing in future by adding a -Wwarn flag to them. I think this should resolve the objections.

[MangoIV]

There’s even a better option: just don’t use the package stanza at all: https://cabal.readthedocs.io/en/stable/cabal-project-description-file.html#package-configuration-options