fix(docker) fix Docker warnings

docker-compose.yml

@@ -1,5 +1,3 @@
-version: '3.5'
-
 services:
     # Frontend
     web:

jigasi/Dockerfile

@@ -8,7 +8,7 @@ LABEL org.opencontainers.image.url="https://github.com/jitsi/jigasi"
 LABEL org.opencontainers.image.source="https://github.com/jitsi/docker-jitsi-meet"
 LABEL org.opencontainers.image.documentation="https://jitsi.github.io/handbook/"
 
-ENV GOOGLE_APPLICATION_CREDENTIALS /config/key.json
+ENV GOOGLE_APPLICATION_CREDENTIALS=/config/key.json
 
 RUN apt-dpkg-wrap apt-get update && \
     apt-dpkg-wrap apt-get install -y jigasi jq jitsi-autoscaler-sidecar && \