Always use python3 during molecule testing

Python2 went out of style more than a decade ago, and was "sunset"
over four years ago, 2020-01-01.

Sure CentOS might have some additional python2 support thanks to
RedHat, but you know what else it has? Python3. And with
epel-release, we get access to python3-PyMySQL, which allows us to
keep things simple.

The geerlingguy centos7 comes without python3, so we can either
drop it, or roll our own. This is the roll-your-own approach.

Grab the latest packaged molecule 4 release and the latest
molecule-docker straight from git. There's a fix that went in after
2.1.0 (cb1c1c31a4a468fb243fc2000656504a3ca00bb3) that fixes a bug
where the molecule.yml would get overwritten during image building.

.github/workflows/proxy.yml

@@ -20,15 +20,33 @@ jobs:
       fail-fast: false
       matrix:
         container:
-          - rockylinux9
-          - rockylinux8
-          - centos7
-          - ubuntu2204
-          - ubuntu2004
-          - ubuntu1804
-          - debian12
-          - debian11
-          - debian10
+          - name: rockylinux9
+            base_image: rockylinux/rockylinux:9-ubi-init
+            os_family: redhat
+          - name: rockylinux8
+            base_image: rockylinux/rockylinux:8-ubi-init
+            os_family: redhat
+          - name: centos7
+            base_image: centos/systemd:latest
+            os_family: redhat
+          - name: ubuntu2204
+            base_image: ubuntu:22.04
+            os_family: debian
+          - name: ubuntu2004
+            base_image: ubuntu:20.04
+            os_family: debian
+          - name: ubuntu1804
+            base_image: ubuntu:18.04
+            os_family: debian
+          - name: debian12
+            base_image: debian:12
+            os_family: debian
+          - name: debian11
+            base_image: debian:11
+            os_family: debian
+          - name: debian10
+            base_image: debian:10
+            os_family: debian
         collection_role:
           - zabbix_proxy
         database:
@@ -39,12 +57,11 @@ jobs:
           - v64
           - v62
           - v60
-        include:
-          - interpreter: python3
-          - interpreter: python
-            container: centos7
         exclude:
-          - container: debian12
+          - container:
+              name: debian12
+              base_image: debian:12
+              os_family: debian
             version: v62
     steps:
       - name: Check out code
@@ -78,10 +95,9 @@ jobs:
 
       - name: Run role tests
         run: >-
-          MY_MOLECULE_CONTAINER=${{ matrix.container }}
-          MY_MOLECULE_IMAGE=${{ matrix.container }}
+          MY_MOLECULE_CONTAINER=${{ matrix.container.name }}
+          MY_MOLECULE_IMAGE=${{ matrix.container.base_image }}
+          MY_MOLECULE_OS_FAMILY=${{ matrix.container.os_family }}
           MY_MOLECULE_VERSION=${{ matrix.version }}
           MY_MOLECULE_DATABASE=${{ matrix.database }}
-          MY_MOLECULE_INTERPRETER=${{ matrix.interpreter }}
-          MY_MOLECULE_DOCKER_COMMAND=${{ matrix.command }}
           molecule test -s ${{ matrix.collection_role }}

molecule/zabbix_proxy/Dockerfile.debian.j2

@@ -0,0 +1,3 @@
+FROM {{ item.base_image }}
+RUN apt-get update && DEBIAN_FRONTEND=noninteractive apt-get install -y python3-pip systemd-sysv
+CMD ["/sbin/init"]

molecule/zabbix_proxy/Dockerfile.redhat.j2

@@ -0,0 +1,3 @@
+FROM {{ item.base_image }}
+RUN yum install -y python3-pip
+CMD ["/sbin/init"]

molecule/zabbix_proxy/molecule.yml

@@ -3,10 +3,11 @@ driver:
   name: docker
 platforms:
   - name: zabbix-proxy-${MY_MOLECULE_VERSION:-v64}-${MY_MOLECULE_DATABASE:-mysql}-${MY_MOLECULE_CONTAINER:-rockylinux8}
-    image: geerlingguy/docker-${MY_MOLECULE_IMAGE:-rockylinux8}-ansible:latest
+    dockerfile: Dockerfile.${MY_MOLECULE_OS_FAMILY:-redhat}.j2
+    base_image: ${MY_MOLECULE_IMAGE:-rockylinux/rockylinux:8-ubi-init}
+    image: ${MY_MOLECULE_CONTAINER:-rockylinux8}
     privileged: true
-    pre_build_image: true
-    command: ${MOLECULE_DOCKER_COMMAND:-""}
+    command: /sbin/init
     networks:
       - name: zabbix
     volumes:
@@ -22,10 +23,8 @@ provisioner:
     ANSIBLE_ROLES_PATH: $HOME/.ansible/collections/ansible_collections/community/zabbix/roles
   inventory:
     group_vars:
-      python3:
+      all:
         ansible_python_interpreter: /usr/bin/python3
-      python:
-        ansible_python_interpreter: /usr/bin/python
       v64:
         zabbix_proxy_version: 6.4
       v62: