Fix a few indentation mistakes (#1752)

Signed-off-by: David Florness <david@florness.com>

build/docker/docker-compose.polylith.yml

@@ -70,7 +70,7 @@ services:
     volumes:
       - ./config:/etc/dendrite
     networks:
-        - internal
+      - internal
 
   signing_key_server:
     hostname: signing_key_server
@@ -86,9 +86,9 @@ services:
     image: matrixdotorg/dendrite-polylith:latest
     command: userapi
     volumes:
-        - ./config:/etc/dendrite
+      - ./config:/etc/dendrite
     networks:
-        - internal
+      - internal
 
   appservice_api:
     hostname: appservice_api