test: use active Python for release packaging test

- pass sys.executable to release-package.sh through PYTHON

- include captured stdout and stderr when the integration script fails

Author: Kingson4Wu

tests/test_release.py

@@ -3,8 +3,10 @@
 from __future__ import annotations
 
 import io
+import os
 import shutil
 import subprocess
+import sys
 import tarfile
 from pathlib import Path
 from types import SimpleNamespace
@@ -174,13 +176,20 @@ def fake_download(url, dest):
 
 def test_release_package_excludes_python_cache_files():
     repo = Path(__file__).resolve().parents[1]
-    subprocess.run(
+    env = os.environ.copy()
+    env["PYTHON"] = sys.executable
+    result = subprocess.run(
         ["bash", "scripts/release-package.sh", "v9.9.9"],
         cwd=repo,
-        check=True,
+        env=env,
         capture_output=True,
         text=True,
     )
+    assert result.returncode == 0, (
+        f"release-package.sh failed with {result.returncode}\n"
+        f"stdout:\n{result.stdout}\n"
+        f"stderr:\n{result.stderr}"
+    )
 
     archive = repo / "dist" / "git-auto-sync-v9.9.9-release.tar.gz"
     with tarfile.open(archive, "r:gz") as tf: