build: configure release-please (GoogleCloudPlatform#131)

Author: JustinBeckwith

.github/release-please.yml

@@ -0,0 +1,2 @@
+releaseType: node
+handleGHRelease: true

.github/workflows/release.yaml

@@ -0,0 +1,17 @@
+on:
+  release:
+    types: [published]
+name: release
+jobs:
+  release-please:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-node@v2
+        with:
+          node-version: 14
+          registry-url: 'https://wombat-dressing-room.appspot.com'
+      - run: npm ci
+      - run: npm publish
+        env:
+          NODE_AUTH_TOKEN: ${{secrets.NPM_TOKEN}}