Add GCP Run button

Author: callingmybluff

README.md

@@ -62,7 +62,7 @@ Doccano can be deployed to AWS ([Cloudformation](https://docs.aws.amazon.com/AWS
 
 If you have a very small team, Doccano can also be deployed to GCP ([Cloud Run](https://cloud.google.com/run)) by clicking on the button below:
 
-https://console.cloud.google.com/cloudshell/editor?shellonly=true&cloudshell_image=gcr.io/cloudrun/doccano&cloudshell_git_repo=https://github.com/chakki-works/doccano.git
+[![GCP Cloud Run PNG Button](https://storage.googleapis.com/gweb-cloudblog-publish/images/run_on_google_cloud.max-300x300.png)](https://console.cloud.google.com/cloudshell/editor?shellonly=true&cloudshell_image=gcr.io/cloudrun/doccano&cloudshell_git_repo=https://github.com/chakki-works/doccano.git)
 
 > Note: Although this is a very cheap option, it is only suitable for very small teams (up to 80 concurrent requests). Read more on [Cloud Run docs](https://cloud.google.com/run/docs/concepts).