fix: ubuntu16 pre-build container (#16)

.github/workflows/testing.yml

@@ -6,8 +6,13 @@ jobs:
   molecule-packaging-tests:
     name: Launch molecule tests with infra-agent package
     runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        # test building and using pre-build containers.
+        build_docker: ["true",""]
     env:
-      TESTING: 'true'
+      TESTING: ${{ matrix.build_docker}}
     steps:
       - uses: actions/checkout@v2
 

prepare_platform.sh

@@ -63,6 +63,13 @@ set_platforms_config() {
             yq -i ".platforms[] |= select(.name == \"$PLATFORM\") += {\"image\":\"$PLATFORM\", \"dockerfile\": \"./dockerfiles/$PLATFORM\"}" $FILE_PATH
         else
             yq -i ".platforms[] |= select(.name == \"$PLATFORM\") += {\"image\":\"ghcr.io/newrelic/pkg-installation-testing-action-$PLATFORM\"}" $FILE_PATH
+
+            # Prevent molecule to install extra tools in the pre-build image
+            # https://ansible.readthedocs.io/projects/molecule/guides/custom-image/
+            # ubuntu16 python 2 installation was being corrupted by this behaivor.
+            if [[ $PLATFORM == "ubuntu1604" ]]; then
+                yq -i ".platforms[] |= select(.name == \"$PLATFORM\") += {\"pre_build_image\": true}" $FILE_PATH
+            fi
         fi
 
         # debian based distributions need to set up the init command