Add a GitHub workflow for building a snapshot release

.github/workflows/release-snapshot.yml

@@ -0,0 +1,32 @@
+name: Release (Snapshot)
+on:
+  push:
+    branches: [ "master", "develop" ]
+  pull_request:
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Install Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: 1.15
+      - name: Install Node.js
+        uses: actions/setup-node@v1
+        with:
+          node-version: '10.x'
+      - name: Install Elm
+        uses: jorelali/setup-elm@v2
+        with:
+          elm-version: 0.19.1
+      - name: Build frontend
+        run: |
+          npm ci
+          npm run build
+        working-directory: ./ui
+      - name: Build release artifacts
+        uses: goreleaser/goreleaser-action@v2
+        with:
+          version: latest
+          args: release --snapshot