Update x/observer/types/observer_set.go

Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>

x/observer/types/observer_set.go

@@ -23,7 +23,7 @@ func (m *ObserverSet) Validate() error {
 	for _, observerAddress := range m.ObserverList {
 		_, err := sdk.AccAddressFromBech32(observerAddress)
 		if err != nil {
-			return err
+			return errors.Wrapf(err, "invalid observer address: %s", observerAddress)
 		}
 	}
 	// Check for duplicates