Update gatsby-config.js

Author: thejustinwalsh

gatsby-config.js

@@ -29,7 +29,7 @@ module.exports = {
         background_color: `#FFFFFF`,
         theme_color: `#FFFFFF`,
         display: `minimal-ui`,
-        icon: `src/images/favicon.ico`, // This path is relative to the root of the site.
+        icon: `src/images/apple-touch-icon.png`, // This path is relative to the root of the site.
       },
     },
     `gatsby-plugin-typescript`,