Pin twine version in workflow.

Co-authored-by: Brigitta Sipocz <bsipocz@gmail.com>

.github/workflows/publish.yml

@@ -18,15 +18,14 @@ jobs:
         python-version: 3.8
 
     - name: Install python-build and twine
-      run: python -m pip install build twine
+      run: python -m pip install build twine>=3.3
 
     - name: Build package
       run: python -m build --sdist --wheel .
 
     - name: List result
       run: ls -l dist
 
-    # Only twine>=3.3 has --strict
     - name: Check long_description
       run: python -m twine check --strict dist/*