docs: contact support to change cloud env var (#49555)

* docs: cloud environment variables

* Apply suggestions from code review

Co-authored-by: Jeff Bruemmer <jeff.bruemmer@gmail.com>

---------

Co-authored-by: Jeff Bruemmer <jeff.bruemmer@gmail.com>

docs/dashboards/subscriptions.md

@@ -80,7 +80,7 @@ If you check this box, Metabase will drop any visualization settings applied to
 
 Here you can specify which questions Metabase should attach results for.
 
-The attached files will include up to 2000 rows by default. If you're self-hosting Metabase, you can adjust this row limit by setting the environment variable [MB_UNAGGREGATED_QUERY_ROW_LIMIT](../configuring-metabase/environment-variables.md#mb_unaggregated_query_row_limit).
+The attached files will include up to 2000 rows by default. If you're self-hosting Metabase, you can adjust this row limit by setting the environment variable [MB_UNAGGREGATED_QUERY_ROW_LIMIT](../configuring-metabase/environment-variables.md#mb_unaggregated_query_row_limit). To change this row limit on your Metabase Cloud instance, you can [contact us](https://www.metabase.com/help/premium) and request a different row limit.
 
 ## Slack subscription options
 

src/metabase/cmd/resources/env-var-intro.md

@@ -43,6 +43,10 @@ Docker:
 docker run -d -p 3000:3000 -e MB_SITE_NAME="Awesome Company" --name metabase metabase/metabase
 ```
 
+## Environment variables on Metabase Cloud
+
+If you're running Metabase Cloud, you can [contact support](https://www.metabase.com/help/premium) to adjust environment variables for your Metabase.
+
 ---
 
 ## List of environment variables