@expectedException and @expectedException tags are replaced with best practice alternatives.

This change records reflects the changes made in

https://www.drupal.org/node/2822837

Regarding test code,

Using @expectedException is not considered good testing practice because you cannot specify where exactly in the test method the exception should be triggered. Background info: https://thephp.cc/news/2016/02/questioning-phpunit-best-practices

In short, tags that once appeared in test methods annotations have been removed and an equivalent code snippets inserted into the method.

For example:

   * @expectedException \Drupal\contact\MailHandlerException
   * @expectedExceptionMessage Unable to determine message recipient

becomes

  $this->setExpectedException(MailHandlerException::class, 'Unable to determine message recipient');

Ideally move this calling function as near as possible to the actual code you want to test, to make it obvious where the exception is expected to be thrown.