add hangouts bridge by copying facebook bridge and find-replacing

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

@@ -0,0 +1,10 @@
+---
+
+- name: Fail if required settings not defined
+  fail:
+    msg: >-
+      You need to define a required configuration setting (`{{ item }}`).
+  when: "vars[item] == ''"
+  with_items:
+    - "matrix_mautrix_hangouts_appservice_token"
+    - "matrix_mautrix_hangouts_homeserver_token"