Try setting up gitpod for building for each PR to ease reviewing (#680)

* Try setting up gitpod

Building on example at publiclab/image-sequencer#1668

* Update .gitpod.yml

.gitpod.yml

@@ -0,0 +1,17 @@
+tasks:
+  - init: npm i && npm run setup
+    command: npm run serve:dev
+ports:
+  - port: 3000
+    onOpen: open-preview
+
+github:
+  prebuilds:
+    main: true
+    branches: true
+    pullRequests: true
+    pullRequestsFromForks: true
+    addCheck: true
+    addComment: true
+    addBadge: false
+    addLabel: false