fix: Do not ignore stderr in case there is a problem in a git call. (#416)

Previously Griffe was only printing the output of stdout in case there was a problem in a git call. This commit implements printing the stderr along with stdout.

Issue-415: #415
PR-416: #416

Author: mabdullahsoyturk

src/griffe/_internal/git.py

@@ -34,7 +34,7 @@ def _normalize(value: str) -> str:
 
 
 def _git(*args: str, check: bool = True) -> str:
-    process = subprocess.run(["git", *args], check=False, text=True, capture_output=True)
+    process = subprocess.run(["git", *args], check=False, text=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
     if check and process.returncode != 0:
         raise GitError(process.stdout.strip())
     return process.stdout.strip()