Update source/reference/method/db.collection.createIndexes.txt

Co-authored-by: jeff-allen-mongo <[email protected]>

Author: ianf-mongodb

source/reference/method/db.collection.createIndexes.txt

@@ -39,6 +39,7 @@ Definition
         - document
 
         - .. _key_patterns:
+        
           An array containing index specification documents. Each document
           contains field and value pairs where the field is
           the index key and the value describes the type of index for that