Update build_documentation.yml

.github/workflows/build_documentation.yml

@@ -8,6 +8,9 @@ on:
 jobs:
   build:
     runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        python-version: ["3.10"]
 
     steps:
       - uses: actions/checkout@v2
@@ -15,7 +18,7 @@ jobs:
       - name: Set up Python ${{ matrix.python-version }}
         uses: actions/setup-python@v2
         with:
-          python-version: "3.10"
+          python-version: ${{ matrix.python-version }}
 
       - name: Install dependencies
         run: |