Remove CVE from jq (undeeded) and improve healthcheck

pica-mattermost/Dockerfile

@@ -13,7 +13,6 @@ ARG PGID=5000
 RUN apk add --no-cache \
 	ca-certificates \
 	curl \
-	jq \
 	libc6-compat \
 	libffi-dev \
   libcap \
@@ -37,12 +36,14 @@ RUN mkdir -p /mattermost/data /mattermost/plugins /mattermost/client/plugins \
 USER mattermost
 
 #Healthcheck to make sure container is ready
-HEALTHCHECK CMD curl --fail http://localhost:8000 || exit 1
+HEALTHCHECK --interval=5m --timeout=3s CMD curl --fail http://localhost:8000//api/v4/system/ping || exit 1
 
 # Configure entrypoint and command
 COPY entrypoint.sh /
 ENTRYPOINT ["/entrypoint.sh"]
 
+RUN chmod +x /entrypoint.sh
+
 WORKDIR /mattermost
 CMD ["mattermost"]