Fix replace section in composer.json

Add first replace to match extension key and second to
communicate that this is a replacement for the TER extension.

Author: helhum

composer.json

@@ -21,6 +21,7 @@
     }
   },
   "replace": {
-    "cobweb/linkhandler": "*"
+    "linkhandler": "self.version",
+    "typo3-ter/linkhandler": "self-version"
   }
 }