fixed typo in usage.md

docs/book/v1/usage.md

@@ -67,6 +67,6 @@ Fixtures can we ordered using 2 methods :
 - by order
 - by dependencies
 
-Please refer to this link for further details on ordering fixtures:
+Please refer to this link for further details on ordering fixtures :
 
 https://www.doctrine-project.org/projects/doctrine-data-fixtures/en/latest/how-to/fixture-ordering.html#fixture-ordering