typo fix

Author: apinnick

_topic_map.yml

@@ -2049,7 +2049,7 @@ Topics:
   File: about-migrating-from-3-to-4
 - Name: Differences between OpenShift Container Platform 3 and 4
   File: planning-migration-3-4
-- Name: About the Migration Toolkit for Containers
+- Name: About MTC
   File: about-mtc-3-4
 - Name: Installing MTC
   File: installing-3-4