Update README.md

Correct a small typo.

README.md

@@ -75,7 +75,7 @@ Allowed values - `'pie', 'bar', 'line', 'point', 'area'`
   lineCurveType: 'cardinal', // change this as per d3 guidelines to avoid smoothline
   isAnimate: true, // run animations while rendering chart
   yAxisTickFormat: 's', //refer tickFormats in d3 to edit this value
-  xAxisMaxTicks: 7 // Optional: maximum number of X axis ticks to show if data points exceed this number
+  xAxisMaxTicks: 7, // Optional: maximum number of X axis ticks to show if data points exceed this number
   yAxisTickFormat: 's', // refer tickFormats in d3 to edit this value
   waitForHeightAndWidth: false // if true, it will not throw an error when the height or width are not defined (e.g. while creating a modal form), and it will be keep watching for valid height and width values
 };