Add a comment explaining why we now have to set ANSIBLE_ROLES_PATH

Author: jsf9k

molecule/default/molecule.yml

@@ -223,6 +223,11 @@ platforms:
 provisioner:
   name: ansible
   env:
+    # Molecule used to add ${MOLECULE_PROJECT_DIRECTORY}/. to this
+    # path for us pre-25.2.0, but now we have to do it ourselves.  See
+    # ansible/molecule#4380 and
+    # https://github.com/ansible/molecule/releases/tag/v25.2.0 for
+    # more details.
     ANSIBLE_ROLES_PATH: ~/.cache/molecule/skeleton-ansible-role/${MOLECULE_SCENARIO_NAME}/roles:${MOLECULE_PROJECT_DIRECTORY}/..:~/.ansible/roles:/usr/share/ansible/roles:/etc/ansible/roles
 scenario:
   name: default