Update source/release-notes.txt

Co-authored-by: Ashley Brown <[email protected]>

Author: sarah-olson-mongodb

source/release-notes.txt

@@ -20,7 +20,7 @@ New features:
 - Support for connecting to a SQL Server Named Instance.
 - Collection names now show for JSON schema files created from the :guilabel:`Code Generation` screen.
 
-Bug Fixes:
+Bug fixes:
 
 - Fixes a post-sync job issue where data verification sometimes stops 
   or displays as not started.