Integrate GitHub actions for auto-releasing 'medea-demo' Helm chart

.github/workflows/release-medea-demo-helm-chart.yml

@@ -0,0 +1,28 @@
+name: Release 'medea-demo' Helm chart
+
+on:
+  push:
+    branches: ["master"]
+    paths:
+      - jason/demo/chart/medea-demo/Chart.yaml
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@master
+        with:
+          ref: ${{ github.ref }}
+          # Required due to not working with out-of-the-box GITHUB_TOKEN:
+          # https://github.community/t5/GitHub-Actions/Github-action-not-triggering-gh-pages-upon-push/td-p/26869
+          token: ${{ secrets.GH_ACCESS_TOKEN }}
+
+      - name: Prepare environment
+        run: |
+          git config --local user.email "[email protected]"
+          git config --local user.name "GitHub Actions"
+
+          make helm.init client-only=yes
+
+      - run: make helm.package.release chart=medea-demo build=yes

Makefile

@@ -25,8 +25,6 @@ RUST_BETA_VER := 1.39-beta.5
 CHROME_VERSION := 77.0
 FIREFOX_VERSION := 69.0
 
-CURRENT_GIT_BRANCH := $(strip $(shell git branch | grep \* | cut -d ' ' -f2))
-
 crate-dir = .
 ifeq ($(crate),medea-jason)
 crate-dir = jason
@@ -819,7 +817,7 @@ endif
 		git commit -m \
 			"Release $(helm-chart)-$(helm-package-release-ver) Helm chart" ; \
 	fi
-	git checkout $(CURRENT_GIT_BRANCH)
+	git checkout -
 	git push origin gh-pages