[Tests] Fix spelling

Author: jbampton

__tests__/PropTypesProductionStandalone-test.js

@@ -163,7 +163,7 @@ describe('PropTypesProductionStandalone', function() {
   });
 
   describe('React ElementType Type', function() {
-    it('shoud be a no-op', function() {
+    it('should be a no-op', function() {
       expectThrowsInProduction(PropTypes.elementType.isRequired, false);
       expectThrowsInProduction(PropTypes.elementType.isRequired, {});
     });