[Collabora] Mount a tmpfs on /opt as it's modified by collabora on each run.

docker-compose.yml

@@ -103,3 +103,5 @@ services:
     volumes:
       - type: tmpfs
         target: /tmp:exec
+      - type: tmpfs
+        target: /opt:exec

images/ngx/nginx.conf

@@ -184,8 +184,5 @@ http {
         location / {
             try_files $uri $uri/ /index.php$request_uri;
         }
-        location /simliveradio {
-            proxy_pass http://simliveradio.stream.laut.fm/simliveradio;
-        }
     }
 }