ci: Capitalize Python consistently

.github/workflows/main.yml

@@ -33,7 +33,7 @@ jobs:
         with:
           python-version: ${{ matrix.python-version }}
 
-      - name: Get full python version
+      - name: Get full Python version
         id: full-python-version
         shell: bash
         run: echo ::set-output name=version::$(python -c "import sys; print('-'.join(str(v) for v in sys.version_info))")