Update submit-mapping-request.md

Minor fix

Author: hsutaiyu

docs/pos/how-to/bridging/ethereum-polygon/submit-mapping-request.md

@@ -6,8 +6,7 @@ Token mapping is important in order to enable the transfer mechanism for the sai
 
 !!! info
 
-    - For more information on how bridging works in the background, see [the doc available here](../index.md).
-    - Thinking about bridging another popular token? Refer to the [reference guide on Polygon Portal](../../../../tools/wallets/portal.md).
+    Thinking about bridging a popular token? Refer to the [reference guide on Polygon Portal](../../../../tools/wallets/portal.md).
 
 ## Steps to submit a mapping request