tests: factor out base nginx-proxy config

test/test_virtual-path/test_forwarding.yml

@@ -1,4 +1,11 @@
 services:
+  nginx-proxy:
+    volumes:
+      - /var/run/docker.sock:/tmp/docker.sock:ro
+      - ${PYTEST_MODULE_PATH}/certs:/etc/nginx/certs:ro
+    environment:
+      DEFAULT_ROOT: "301 http://$$host/web1$$request_uri"
+
   web1:
     image: web
     expose:
@@ -8,11 +15,3 @@ services:
       VIRTUAL_HOST: "www.nginx-proxy.tld"
       VIRTUAL_PATH: "/web1/"
       VIRTUAL_DEST: "/"
-
-  sut:
-    image: nginxproxy/nginx-proxy:test
-    volumes:
-      - /var/run/docker.sock:/tmp/docker.sock:ro
-      - ./certs:/etc/nginx/certs:ro
-    environment:
-      - DEFAULT_ROOT=301 http://$$host/web1$$request_uri