molecule scenario to test upgrading from releases

Provide a separate scenario to install the last release, then update to
the current one.
Also includes improved deployment verification (check if uploading a
.txt through the API works).

ansible/molecule/default/converge.yml

@@ -1,7 +0,0 @@
----
-- name: Converge
-  hosts: all
-  tasks:
-    - name: "Include ansible"
-      include_role:
-        name: "ansible"

ansible/molecule/default/molecule.yml

@@ -1,35 +0,0 @@
----
-dependency:
-  name: galaxy
-driver:
-  name: docker
-platforms:
-  - name: ubuntu_focal
-    image: jrei/systemd-ubuntu:20.04
-    privileged: true
-    volumes:
-      - /sys/fs/cgroup:/sys/fs/cgroup:ro
-    tmpfs:
-      - /tmp
-      - /run
-      - /run/lock
-    override_command: False
-  # ubuntu 18.04 bionic works except that
-  #   the default redis configuration expects IPv6 which is not enabled in docker by default
-  #   the default Python environment is configured for ASCII instead of UTF-8
-  # ubuntu 16.04 xenial only has Python 3.5 which is EOL and breaks multiple dependencies
-  - name: debian_buster
-    image: jrei/systemd-debian:10
-    privileged: true
-    volumes:
-      - /sys/fs/cgroup:/sys/fs/cgroup:ro
-    tmpfs:
-      - /tmp
-      - /run
-      - /run/lock
-    override_command: False
-  # debian 9 stretch only has Python 3.5 which is EOL and breaks multiple dependencies
-provisioner:
-  name: ansible
-verifier:
-  name: ansible

ansible/molecule/default/verify.yml

@@ -1,14 +0,0 @@
----
-# This is an example playbook to execute Ansible tests.
-
-- name: Verify
-  hosts: all
-  gather_facts: false
-  tasks:
-  - name: check if webserver is up
-    uri:
-      url: http://localhost:8000
-      status_code: [200, 302]
-      return_content: yes
-    register: landingpage
-    failed_when: "'Sign in</button>' not in landingpage.content"