check if matrix_vars.yml file exists

roles/matrix-awx/tasks/rename_variables.yml

@@ -1,9 +1,13 @@
 
+- name: Check if matrix_vars.yml file exists
+  stat:
+    path: "/var/lib/awx/projects/clients/{{ member_id }}/{{ subscription_id }}/matrix_vars.yml"
+  register: matrix_vars_file
+
 - name: Rename synapse presence variable
   delegate_to: 127.0.0.1
   replace:
     path: "/var/lib/awx/projects/clients/{{ member_id }}/{{ subscription_id }}/matrix_vars.yml"
     regexp: 'matrix_synapse_use_presence'
     replace: 'matrix_synapse_presence_enabled'
-  args: 
-    creates: "/var/lib/awx/projects/clients/{{ member_id }}/{{ subscription_id }}/matrix_vars.yml"
+  when: matrix_vars_file.stat.exists