Use g for formatting floating point timeouts

The timeout error message formats `timeout` with `%d`, but `kill_after_timeout` is typed as `float` and is commonly passed as a non-integer (e.g., 0.1). This can produce a misleading message (truncation to 0) and may raise a formatting error depending on Python behavior. Format it as a float (or generic number) instead.

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

Author: Byron

git/cmd.py

@@ -1473,10 +1473,7 @@ def kill_process(pid: int) -> None:
                 return
 
             def make_timeout_error() -> Union[str, bytes]:
-                err = 'Timeout: the command "%s" did not complete in %d secs.' % (
-                    " ".join(redacted_command),
-                    timeout,
-                )
+                err = f'Timeout: the command "{" ".join(redacted_command)}" did not complete in {timeout:g} secs.'
                 return err if universal_newlines else err.encode(defenc)
 
             def communicate() -> Tuple[AnyStr, AnyStr]: