Update README.md

Actually make the button

Author: aazaibi-MW

README.md

@@ -1,7 +1,7 @@
 # Gantt Chart
 
 [![View Gantt Chart on File Exchange](https://www.mathworks.com/matlabcentral/images/matlab-file-exchange.svg)](https://www.mathworks.com/matlabcentral/fileexchange/116970-gantt-chart)
-(https://www.mathworks.com/matlabcentral/fileexchange/116970-gantt-chart) [![Open in MATLAB Online]
+[![Open in MATLAB Online](https://www.mathworks.com/images/responsive/global/open-in-matlab-online.svg)](https://matlab.mathworks.com/open/github/v1?host=www.mathworks.com&repo=matlabcentral/fileexchange)
 
 Version: 1.0