fix: Run bot as a module to fix import error

Author: LMLK-seal

.github/workflows/gitbit_bot.yml

@@ -29,4 +29,4 @@ jobs:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           GITHUB_EVENT_PATH: ${{ github.event_path }}
           GITHUB_REPOSITORY: ${{ github.repository }}
-        run: python gitbit/main.py
+        run: python -m gitbit.main