Improve docs for opening Gitpod workspaces

Signed-off-by: ArthurSens <[email protected]>

Author: ArthurSens

developer-workspace/README.md

@@ -27,3 +27,8 @@ If you are working on new features/bug fixes, you can regenerate kube-prometheus
 Gitpod is already available to everyone to use for free. It can also run commands that we speficy in the `.gitpod.yml` file located in the root directory of the git repository, so even the cluster creation can be fully automated.
 
 You can use the same workflow as mentioned in the [Codespaces](#Codespaces) section, however Gitpod doesn't have native support for any kubernetes distribution. The workaround is to create a full QEMU Virtual Machine and deploy [k3s](https://github.com/k3s-io/k3s) inside this VM. Don't worry, this whole process is already fully automated, but due to the workaround the whole workspace may be very slow.
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+To open up a workspace with Gitpod, you can install the [Google Chrome extension](https://www.gitpod.io/docs/browser-extension/) to add a new button to Github UI and use it on PRs or from the main page. Or by directly typing in the browser `http://gitpod.io/#https://github.com/prometheus-operator/kube-prometheus/pull/<Pull Request Number>` or just `http://gitpod.io/#https://github.com/prometheus-operator/kube-prometheus`
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+![image](https://user-images.githubusercontent.com/24193764/135534546-4f6bf0e5-57cd-4e35-ad80-88bd47d64276.png)
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