update onboarding docs (#3680)

Author: sungchun12

docs/cloud/tcloud_getting_started.md

@@ -64,11 +64,13 @@ First, open a terminal within your terminal/IDE (ex: VSCode). Then follow the fo
 2. Create a new file called `requirements.txt` and add `tcloud` to it:
 
     ```bash
-    echo 'tcloud==1.3.0' > requirements.txt
+    echo 'tcloud' > requirements.txt
     ```
 
     > Pypi source: [tcloud](https://pypi.org/project/tcloud/)
 
+    > Note: your Tobiko Solutions Architect will provide you a pinned version of `tcloud`
+
 3. Create a Python virtual environment and install `tcloud`:
 
     ```bash linenums="1"
@@ -174,13 +176,8 @@ Now we're ready to connect your data warehouse to Tobiko Cloud:
     ```yaml linenums="1"
     gateways:
       tobiko_cloud: # this will use the config in tcloud.yaml for state_connection
-        connection:
-          type: bigquery
-          method: service-account-json
-          concurrent_tasks: 5
-          register_comments: true
-          keyfile_json: {{ env_var('GOOGLE_SQLMESH_CREDENTIALS') }} # uses the value in the GOOGLE_SQLMESH_CREDENTIALS environment variable
-          project: sqlmesh-public-demo
+        scheduler: # TODO: add the connection in the Tobiko Cloud Connections Page with the credentials for your data warehouse
+          type: cloud
 
     default_gateway: tobiko_cloud