Update "Open in Cloud Shell" links (GoogleCloudPlatform#4771)

Author: davidcavazos

dataflow/README.md

@@ -1,6 +1,6 @@
 # Getting started with Google Cloud Dataflow
 
-[![Open in Cloud Shell](http://gstatic.com/cloudssh/images/open-btn.svg)](https://console.cloud.google.com/cloudshell/editor)
+[![Open in Cloud Shell](http://gstatic.com/cloudssh/images/open-btn.svg)](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/GoogleCloudPlatform/python-docs-samples&page=editor&open_in_editor=dataflow/README.md)
 
 [Apache Beam](https://beam.apache.org/)
 is an open source, unified model for defining both batch and streaming data-parallel processing pipelines.

dataflow/encryption-keys/README.md

@@ -1,6 +1,6 @@
 # Using customer-managed encryption keys
 
-[![Open in Cloud Shell](http://gstatic.com/cloudssh/images/open-btn.svg)](https://console.cloud.google.com/cloudshell/editor)
+[![Open in Cloud Shell](http://gstatic.com/cloudssh/images/open-btn.svg)](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/GoogleCloudPlatform/python-docs-samples&page=editor&open_in_editor=dataflow/encryption-keys/README.md)
 
 This sample demonstrate how to use
 [cryptographic encryption keys](https://cloud.google.com/kms/)

dataflow/flex-templates/streaming_beam/README.md

@@ -1,6 +1,6 @@
 # Dataflow flex templates - Streaming Beam
 
-[![Open in Cloud Shell](http://gstatic.com/cloudssh/images/open-btn.svg)](https://console.cloud.google.com/cloudshell/editor)
+[![Open in Cloud Shell](http://gstatic.com/cloudssh/images/open-btn.svg)](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/GoogleCloudPlatform/python-docs-samples&page=editor&open_in_editor=dataflow/flex-templates/streaming_beam/README.md)
 
 📝 Docs: [Using Flex Templates](https://cloud.google.com/dataflow/docs/guides/templates/using-flex-templates)
 

dataflow/run_template/README.md

@@ -1,6 +1,6 @@
 # Run template
 
-[![Open in Cloud Shell](http://gstatic.com/cloudssh/images/open-btn.svg)](https://console.cloud.google.com/cloudshell/editor)
+[![Open in Cloud Shell](http://gstatic.com/cloudssh/images/open-btn.svg)](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/GoogleCloudPlatform/python-docs-samples&page=editor&open_in_editor=dataflow/run_template/README.md)
 
 This sample demonstrate how to run an
 [Apache Beam](https://beam.apache.org/)