tests: fix virtual path tests for new dhparam

test/test_virtual-path/test_forwarding.yml

@@ -12,7 +12,6 @@ sut:
   image: nginxproxy/nginx-proxy:test
   volumes:
     - /var/run/docker.sock:/tmp/docker.sock:ro
-    - ../lib/ssl/dhparam.pem:/etc/nginx/dhparam/dhparam.pem:ro
     - ./certs:/etc/nginx/certs:ro
   environment:
     - DEFAULT_ROOT=301 http://$$host/web1$$request_uri