`~/.git` breaks installer

## when

## result

```
You have just created a nixos-unified-template flake.nix using home-manager.

• Edit ./modules/home/*.nix to customize your configuration.
• Run nix run to apply the configuration.
• Then, open a new terminal to see your new shell.

Enjoy!
warning: Git tree '/Users/madhubalan.m' is dirty
error:
… while evaluating the attribute 'root.result'
at «flakes-internal»/call-flake.nix:94:7:
93| {
94| result =
| ^
95| if node.flake or true then

… in the left operand of the update (//) operator
at «flakes-internal»/call-flake.nix:75:9:
74| result =
75| outputs
| ^
76| # We add the sourceInfo attribute for its metadata, as they are

(stack trace truncated; use '--show-trace' to show the full, detailed trace)

error: None of these paths exist: nix/modules/flake modules/flake nix/modules/flake-parts modules/flake-parts
```