fix: Improved error messaging for toHaveFocus assertion (#304)

* Improved error message for toHaveFocus assertion
* Updated error message

Co-authored-by: Syneva Runyan <syneva.runyan@mailchimp.com>
Co-authored-by: syneva-runyan <srunyan3@gatech.edu>

src/to-have-focus.js

@@ -13,9 +13,9 @@ export function toHaveFocus(element) {
           '',
         ),
         '',
-        'Expected',
+        'Expected element with focus:',
         `  ${this.utils.printExpected(element)}`,
-        'Received:',
+        'Received element with focus:',
         `  ${this.utils.printReceived(element.ownerDocument.activeElement)}`,
       ].join('\n')
     },