Assume git+ prefix when URLs end in .git (#5868)

## Summary

Right now, this applies _everywhere_, so the following also works:

```
pip install "elmer-circuitbuilder @ https://github.com/ElmerCSC/elmer_circuitbuilder.git"
```

I actually think that's ok?

Closes https://github.com/astral-sh/uv/issues/5866.

crates/pypi-types/src/parsed_url.rs

@@ -347,6 +347,11 @@ impl TryFrom<Url> for ParsedUrl {
                     message: "Unknown scheme",
                 }),
             }
+        } else if Path::new(url.path())
+            .extension()
+            .is_some_and(|ext| ext.eq_ignore_ascii_case("git"))
+        {
+            Ok(Self::Git(ParsedGitUrl::try_from(url)?))
         } else if url.scheme().eq_ignore_ascii_case("file") {
             let path = url
                 .to_file_path()