update the gitpod setup description to be more precise.

Author: nisarhassan12

.gitpod.yml

@@ -1,5 +1,5 @@
 tasks:
-  - init: npm install && npm i gulp -g
+  - before: npm install && npm i gulp -g
     command: gulp
 ports:
   - port: 3000

contributing.md

@@ -29,9 +29,15 @@ Please follow the instructions in our issue templates. Don't use github issues t
 
 * To test locally, you can use the demo site. First make sure you have installed the dependencies with `npm install` or `yarn`. Run `gulp` to build and it will run a local web server for development and watch for any changes.
 
-### Online one-click setup
+### Online one-click setup for contributing
 
-Alternatively can also use Gitpod, a free online Visual Studio Code-like IDE. With a single click it will automatically launch a ready-to-code workspace with all the dependencies pre-installed, gulp watching for changes and the web server running, so that you can start coding straightaway.
+You can use Gitpod (a free online VS Code-like IDE) for contributing. With a single click it will launch a workspace and automatically:
+
+- clone the plyr repo.
+- install the dependencies.
+- run `gulp` to the start the server.
+
+So that you can start straight away.
 
 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)