docs: multiline export (#47925)

* multiline export

* Update docs/installation-and-operation/serialization.md

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

---------

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

docs/installation-and-operation/serialization.md

@@ -142,7 +142,9 @@ See [export parameters in CLI commands](#export-options) or [export parameters i
 
 ### Example of a serialized question
 
-Questions can be found in the `cards` directory of a collection directory. Here's an example card YAML file for a question written with SQL that uses a field filter and has an area chart visualization:
+Questions can be found in the `cards` directory of a collection directory. Here's an example card YAML file for a question written with SQL that uses a field filter and has an area chart visualization.
+
+> To preserve a native query's multi-line format, remove trailing whitespace from native queries. If your native query has trailing whitespace, YAML will convert your query to a single string literal (which only affects presentation, not functionality). 
 
 ```yml
 name: Products by week