check ansible version for self-building in every role

roles/matrix-bridge-mautrix-hangouts/tasks/init.yml

@@ -60,3 +60,10 @@
       URL endpoint to the matrix-mautrix-hangouts container.
       You can expose the container's port using the `matrix_mautrix_hangouts_container_http_host_bind_port` variable.
   when: "matrix_mautrix_hangouts_enabled|bool and (matrix_nginx_proxy_enabled is not defined or matrix_nginx_proxy_enabled|bool == false)"
+
+# ansible lower than 2.8, does not support docker_image build parameters
+# for self buildig it is explicitly needed, so we rather fail here
+- name: Fail if running on Ansible lower than 2.8 and trying self building
+  fail:
+    msg: "To self build Mautrix Hangouts image, you should usa ansible 2.8 or higher. E.g. pip contains such packages."
+  when: "ansible_version.major == 2 and ansible_version.minor < 8 and matrix_mautrix_hangouts_self_build"