GHW for building and publishing docker images (#1391)

* add ghw and scripts for docker image deployment

* debug

* add permissions for content

* fix path to the bin folder

* add tags

* rename env

* fix path to docker file

* make polkadot-parachain executable

* fix typo

* fix more typos

* test

* revert back  use of  working directory

* mke bin executable in the artifacts folder

* use cd instead of working directory

* change path to cash

* fix path to cash

* change cache key

* delete old flows

* addressed PR comments

* fix path

* reorg docker files

docker/scripts/polkadot/test-build.sh

@@ -0,0 +1,18 @@
+#!/usr/bin/env bash
+
+TMP=$(mktemp -d)
+ENGINE=${ENGINE:-podman}
+
+# You need to build an injected image first
+
+# Fetch some binaries
+$ENGINE run --user root --rm -i \
+  -v "$TMP:/export" \
+  --entrypoint /bin/bash \
+  parity/polkadot -c \
+  'cp "$(which polkadot)" /export'
+
+echo "Checking binaries we got:"
+tree $TMP
+
+./build-injected.sh $TMP