[gh action] Release on tag push

.github/actions/commit-matches-branch/Dockerfile

@@ -0,0 +1,16 @@
+FROM debian:stable-slim
+
+LABEL "name"="commit-matches-branch"
+LABEL "version"="1.0.0"
+
+LABEL "com.github.actions.name"="Commit matches branch"
+LABEL "com.github.actions.description"="Only continue the workflow if the current commit is the last commit of the given branch"
+LABEL "com.github.actions.icon"="filter"
+LABEL "com.github.actions.color"="gray-dark"
+
+ADD entrypoint.sh /action/entrypoint.sh
+
+RUN chmod +x /action/entrypoint.sh
+RUN apt-get update && apt-get install -y --no-install-recommends git
+
+ENTRYPOINT ["/action/entrypoint.sh"]

.github/actions/commit-matches-branch/entrypoint.sh

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+#!/bin/sh
+
+set -e
+
+current=$(git rev-parse HEAD)
+git checkout $1
+branch=$(git rev-parse HEAD)
+
+if [ "$current" = "$branch" ]; then
+  exit 0
+else
+  exit 78
+fi