[style] Ignore line break before binary operator

* https://www.python.org/dev/peps/pep-0008/#should-a-line-break-before-or-after-a-binary-operator
* https://www.flake8rules.com/rules/W503.html

.github/workflows/asciinema.yml

@@ -19,7 +19,9 @@ jobs:
         run: pip install build cmarkgfm pycodestyle twine
       - name: Run pycodestyle
         run: >
-          find . -name '*\.py' -exec pycodestyle --ignore=E501,E402,E722 "{}" \+
+          find .
+          -name '*\.py'
+          -exec pycodestyle --ignore=E402,E501,E722,W503 "{}" \+
       - name: Run twine
         run: |
           python3 -m build