feat(build): drop root privileges, update .dockerignore

Author: suprovsky

.dockerignore

@@ -138,13 +138,18 @@ temp/
 test.py
 
 # Other stuff
+.dockerignore
 .env.example
 .gitignore
 .github/
 app.json
 CHANGELOG.md
+docker-compose.yml
+LICENSE
+PRIVACY.md
 Procfile
 pyproject.toml
 README.md
 Pipfile
 Pipfile.lock
+SPONSORS.json

Dockerfile

@@ -14,3 +14,6 @@ COPY --from=build /inst /usr/local
 WORKDIR /modmailbot
 CMD ["python", "bot.py"]
 COPY . /modmailbot
+RUN adduser --disabled-password --gecos '' app && \
+  chown -R app /modmailbot
+USER app