Explicitly test Ansible 2.10.0

.github/workflows/main.yml

@@ -29,7 +29,7 @@ jobs:
           - devel
         include:
           - python: "3.8"
-            ansible: "stable-2.10"
+            ansible: "v2.10.0"
           - python: "3.6"
             ansible: "stable-2.11"
           - python: "3.7"
@@ -67,6 +67,9 @@ jobs:
         if: matrix.container == null
       - name: Install Ansible
         run: pip install --upgrade https://github.com/ansible/ansible/archive/${{ matrix.ansible }}.tar.gz
+      - name: Ensure Jinja version is old enough for Ansible 2.10.0
+        run: pip install --upgrade 'Jinja2<3.1'
+        if: matrix.ansible == 'v2.10.0'
       - name: Install dependencies
         run: make test-setup
       - name: prepare a redhat-uep.pem, even if we run on Ubuntu
@@ -81,7 +84,7 @@ jobs:
         run: make dist-test
       - name: Run sanity tests
         run: make SANITY_OPTS="--docker" sanity
-        if: matrix.ansible != 'stable-2.10' && matrix.ansible != 'stable-2.11'
+        if: matrix.ansible != 'v2.10.0' && matrix.ansible != 'stable-2.11'
 
   checkmode:
     runs-on: ubuntu-latest