Update README.md

Co-authored-by: Cor <[email protected]>

Author: mwojtyczka

README.md

@@ -375,7 +375,7 @@ See also [`log_account_link`](#log_account_link-fixture), [`make_acc_group`](#ma
 ### `spark` fixture
 Get Databricks Connect Spark session. Requires `databricks-connect` package to be installed.
 
-To enable serverless set the local environment variable DATABRICKS_SERVERLESS_COMPUTE_ID to auto.
+To enable serverless set the local environment variable `DATABRICKS_SERVERLESS_COMPUTE_ID` to `"auto"`.
 If this environment variable is set, Databricks Connect ignores the cluster id.
 
 Usage: