fix(semaphore/collections): mount to /opt/ansible-collections, set ANSIBLE_COLLECTIONS_PATHS

/home/semaphore/.ansible/ is owned by root after Podman creates the
bind-mount dir, so ansible-galaxy can't create sibling tmp dirs.
Mount to a neutral /opt/ansible-collections path and point Ansible
at it via ANSIBLE_COLLECTIONS_PATHS env var instead.

ansible/roles/semaphore/tasks/collections.yml

@@ -30,7 +30,7 @@
       podman exec {{ semaphore_container_name }}
       {{ ansible_galaxy_bin.stdout }} collection install
       {{ item.name }}{% if item.version is defined %}:{{ item.version }}{% endif %}
-      -p /home/semaphore/.ansible/collections
+      -p /opt/ansible-collections
       --force
   loop: "{{ semaphore_ansible_collections }}"
   loop_control: