fixed a typo in the test echo message
fixed a typo in the test echo message

BranchMetrics/Smart-App-Banner-Deep-Linking-Web-SDK,BranchMetrics/Smart-App-Banner-Deep-Linking-Web-SDK,BranchMetrics/Smart-App-Banner-Deep-Linking-Web-SDK,BranchMetrics/Smart-App-Banner-Deep-Linking-Web-SDK