chore: gitignore setup.py

The setup.py file is auto-generated by Poetry, since we have
`tool.poetry.build.generate-setup-file = true` set in our pyproject.toml
file.

.gitignore

@@ -135,6 +135,10 @@ ipython_config.py
 #   https://python-poetry.org/docs/basic-usage/#commit-your-poetrylock-file-to-version-control
 #poetry.lock
 
+#   The setup.py file is auto-generated by Poetry if you have
+#   `tool.poetry.build.generate-setup-file = true` set in your pyproject.toml file
+setup.py
+
 # pdm
 #   Similar to Pipfile.lock, it is generally recommended to include pdm.lock in version control.
 #pdm.lock