use key correctly

Author: kchobantonov

packages/examples-react/src/examples/template-layout/uischema.json

@@ -21,7 +21,7 @@
       "elements": [
         {
           "type": "TemplateLayout",
-          "template": "<div>{errors.length > 0 && (<div> {errors.map((error, index) => { if (typeof Message !== 'undefined') { return <div><Message key={index} severity='error' text={error.message} /></div>; } else if (typeof Alert !== 'undefined') { return <div><Alert key={index} message={error.message} type='error' /></div>; } else { return null; } })} </div>)}</div>"
+          "template": "<div>{errors.length > 0 && (<div> {errors.map((error, index) => { if (typeof Message !== 'undefined') { return <div key={index}><Message severity='error' text={error.message} /></div>; } else if (typeof Alert !== 'undefined') { return <div key={index}><Alert message={error.message} type='error' /></div>; } else { return null; } })} </div>)}</div>"
         },
         {
           "type": "VerticalLayout",