ci: pin node version

Author: jerivas

.github/workflows/main.yml

@@ -31,6 +31,9 @@ jobs:
       - uses: actions/setup-python@v2
         with:
           python-version: 3.9
+      - uses: actions/setup-node@v2
+        with:
+          node-version: '14' # https://github.com/cycjimmy/semantic-release-action/issues/79#issuecomment-955463633
       - uses: cycjimmy/semantic-release-action@v2
         with:
           semantic_version: 18