Add trailing-slash redirect for /synapse-admin

roles/matrix-synapse-admin/tasks/init.yml

@@ -15,7 +15,9 @@
   - name: Generate Synapse Admin proxying configuration for matrix-nginx-proxy
     set_fact:
       matrix_synapse_admin_matrix_nginx_proxy_configuration: |
-        location ~ ^{{ matrix_synapse_admin_public_endpoint }}/?(.*) {
+        rewrite ^{{ matrix_synapse_admin_public_endpoint }}$ $scheme://$server_name{{ matrix_synapse_admin_public_endpoint }}/ permanent;
+
+        location ~ ^{{ matrix_synapse_admin_public_endpoint }}/(.*) {
         {% if matrix_nginx_proxy_enabled|default(False) %}
           {# Use the embedded DNS resolver in Docker containers to discover the service #}
           resolver 127.0.0.11 valid=5s;