* CI: Split common functions into lib.sh and make...

... alert_pending_release.sh check the substrate changes for various
labels. If labelled, will be included in the changelog, otherwise will
silently be left out.

* replace non-standard /bin/bash with /usr/bin/env bash

* CI: make lib.sh /bin/sh-compatible

* Fix gitlab release drafting script

Don't scan commit body for PR-like commit messages. Fix warnings from linter,
and take object URL for signing verification from /git/ref/tags rather than hard-coding

* Temporarily Disable GPG verification in pending...

...release alerts. GPG verification of objects is also done before creating the
draft release so this isn't as bad as it sounds

* Temporarily Disable GPG verification in pending...

...release alerts. GPG verification of objects is also done before creating the
draft release so this isn't as bad as it sounds

* Remove accidental GH token leakage 😅

* Add publish_draft_release.sh

This new CI script will generate a list of differences between
this tagged version and the previous tagged version (including
substrate changes), and create a draft release on Github. Once
this is done, the draft release will be posted in Matrix (the
channel is determined by a Gitlab CI environment variable).

* Add highlighting gav for draft release