chore: remove unnecessary legacy handler from qgb module (backport #2635

) (#2647)

This is an automatic backport of pull request #2635 done by
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Co-authored-by: CHAMI Rachid <[email protected]>

x/qgb/module.go

@@ -114,7 +114,7 @@ func (am AppModule) Name() string {
 
 // Route returns the capability module's message routing key.
 func (am AppModule) Route() sdk.Route {
-	return sdk.NewRoute(types.RouterKey, NewHandler(am.keeper))
+	return sdk.Route{}
 }
 
 // QuerierRoute returns the capability module's query routing key.