misc: fix label order in dockerfiles

jigasi/Dockerfile

@@ -1,13 +1,13 @@
+ARG JITSI_REPO=jitsi
+ARG BASE_TAG=latest
+FROM ${JITSI_REPO}/base:${BASE_TAG}
+
 LABEL org.opencontainers.image.title="Jitsi Gateway to SIP (jigasi)"
 LABEL org.opencontainers.image.description="Server-side application that allows regular SIP clients to join conferences."
 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/"
 
-ARG JITSI_REPO=jitsi
-ARG BASE_TAG=latest
-FROM ${JITSI_REPO}/base:${BASE_TAG}
-
 ENV GOOGLE_APPLICATION_CREDENTIALS /config/key.json
 
 # Jigasi doesn't yet work well with Java 11, let's ccontinue to use 8.