chore(docs): remove incorrect answer from FAQ (#26428)

Author: sfirke

docs/docs/frequently-asked-questions.mdx

@@ -175,10 +175,6 @@ non-OLTP databases are not designed for this type of workload.
 You can take a look at this Flask-AppBuilder
 [configuration example](https://github.com/dpgaspar/Flask-AppBuilder/blob/master/examples/oauth/config.py).
 
-### How can I set a default filter on my dashboard?
-
-Simply apply the filter and save the dashboard while the filter is active.
-
 ### Is there a way to force the dashboard to use specific colors?
 
 It is possible on a per-dashboard basis by providing a mapping of labels to colors in the JSON