CI fix: Use python3 with ansible (#94)

* Use python3 with ansible

* Switch to distro that uses python3 be default

This should heopfully prevent us from accidently using python2.

* Install ansible

The system installed ansible can be using python2 in some cases. As python2 is
end of life, it is a bit of a lottery when a pip package drops support for
python2.

Author: jovial

.github/workflows/ci.yml

@@ -10,7 +10,8 @@ jobs:
 
   test:
     name: Molecule
-    runs-on: ubuntu-latest
+    # Select an image that uses python3 by default
+    runs-on: ubuntu-20.04
     strategy:
       fail-fast: false
       matrix:
@@ -57,7 +58,7 @@ jobs:
           python-version: '3.x'
 
       - name: Install test dependencies.
-        run: pip3 install molecule[docker] docker yamllint ansible-lint
+        run: pip3 install -U ansible molecule[docker] docker yamllint ansible-lint
 
       - name: Display ansible version
         run:  ansible --version
@@ -77,7 +78,7 @@ jobs:
 
   runonce:
     name: Checks
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     steps:
       - name: Check out the codebase.
         uses: actions/checkout@v2
@@ -88,7 +89,7 @@ jobs:
           python-version: '3.x'
 
       - name: Install test dependencies.
-        run: pip3 install molecule[docker] docker yamllint ansible-lint
+        run: pip3 install -U ansible molecule[docker] docker yamllint ansible-lint
 
       - name: Display ansible version
         run:  ansible --version