Use minimal git for fetching gems

[edude03]

Motivation for this change

Noticed that using buildRubyGem would pull in a second ruby interpreter due to using "full fat" git, which includes asciidoctor (which brings it's own ruby interpreter)

I patched this locally to see if it would fix the issue and at least in my testing it works just the same, with the benefit of smaller closure size (and faster builds if you don't have that git/asciidoc/ruby combo built already)

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/)
• Determined the impact on package closure size (by running nix path-info -S before and after)
• Ensured that relevant documentation is up to date
• Fits CONTRIBUTING.md.

[r-rmcgibbo]

Result of nixpkgs-review pr 117727 at ae4fac9f run on x86_64-linux 1

1 package skipped due to time constraints:

• mastodon

2 packages built successfully:

• anystyle-cli
• metasploit

---

Result of nixpkgs-review pr 117727 at ae4fac9f run on aarch64-linux 1

2 packages built successfully:

• anystyle-cli
• metasploit

[marsam]

LGTM