Fix git issue in test

Author: hamishmack

nix-tools/.buildkite/nix-tools-build.sh

@@ -42,8 +42,8 @@ echo "There are no tests -- https://github.com/input-output-hk/haskell.nix/issue
 echo
 echo "+++ Add runtime dependencies to PATH"
 
-nix build -f channel:nixos-20.03 nix-prefetch-scripts -o nix-prefetch-scripts
-nix build -f channel:nixos-20.03 git -o git
+nix build -f channel:nixos-22.11 nix-prefetch-scripts -o nix-prefetch-scripts
+nix build -f channel:nixos-22.11 git -o git
 export PATH="$PWD/nix-prefetch-scripts/bin:$PWD/git/bin:$PATH"
 
 echo