Simnet triggers and images (#2714)

* CI: new image for simnet

* CI: chore

* CI: separate image for collator

* dockerfile: it's bad upgrading in the images

* CI: correct links to Dockerfiles

* CI: right dotenv usage

* CI: workaround GitLab's bug that failed trigger status is not reported and 'job runs forever'

* CI: debug: need instead of rules to avoid the bug

* dockerfile: fix storage

* CI: workaround sending the status when the trigger is failed

* CI: fix needed job

* CI: edit comments

* CI: trigger simnet with API

* CI: triggering script

* CI: remove real-overseer

* CI: trigger real simnet

polkadot/scripts/docker/Dockerfile

@@ -3,10 +3,11 @@ FROM debian:buster-slim
 # metadata
 ARG VCS_REF
 ARG BUILD_DATE
+ARG IMAGE_NAME
 
 LABEL io.parity.image.authors="devops-team@parity.io" \
 	io.parity.image.vendor="Parity Technologies" \
-	io.parity.image.title="parity/polkadot" \
+	io.parity.image.title="${IMAGE_NAME}" \
 	io.parity.image.description="polkadot: a platform for web3" \
 	io.parity.image.source="https://github.com/paritytech/polkadot/blob/${VCS_REF}/scripts/docker/Dockerfile" \
 	io.parity.image.revision="${VCS_REF}" \
@@ -18,7 +19,6 @@ ENV RUST_BACKTRACE 1
 
 # install tools and dependencies
 RUN apt-get update && \
-	DEBIAN_FRONTEND=noninteractive apt-get upgrade -y && \
 	DEBIAN_FRONTEND=noninteractive apt-get install -y \
 		libssl1.1 \
 		ca-certificates \
@@ -45,4 +45,3 @@ EXPOSE 30333 9933 9944
 VOLUME ["/polkadot"]
 
 ENTRYPOINT ["/usr/local/bin/polkadot"]
-