fix: update function name to match examples

Author: Planeshifter

lib/node_modules/@stdlib/math/base/assert/int32-is-even/lib/native.js

@@ -45,11 +45,11 @@ var addon = require( './../src/addon.node' );
 * var bool = isEven( 0 );
 * // returns true
 */
-function iseven( x ) {
+function isEven( x ) {
 	return Boolean( addon( x ) );
 }
 
 
 // EXPORTS //
 
-module.exports = iseven;
+module.exports = isEven;