Update to Nix 2.17

Merge pull request #39 from purcell/nix-2.17

Sync with the script changes in install-nix-action@23

Resolve nix-related MacOS issues

v5.0

Add Emacs 29.1 to the CI matrix

Fix for cachix issues

Merge pull request #34 from purcell/nix-2.14-fixes

Incorporate upstream changes from cachix/install-nix-action

v3.0: Merge pull request #16 from purcell/add-path-deprecation

Avoid warnings about deprecated use of add-path etc.

Various updates

v2.0

Merge pull request #9 from purcell/dependabot/npm_and_yarn/actions/ht…

Initial release

v1.0

Add badges to README