Build/Test Tools: Handle removal of `TestCase::getAnnotations()`.

The PHPUnit native `TestCase::getAnnotations()` method is used to check for WP flavored deprecation notices, however, this method was not covered by the backward compatibility promise for PHPUnit (and was annotated as excluded).

The method has been removed as part of an internal refactor in commit [68582043e1 sebastianbergmann/phpunit@6858204], which is included in PHPUnit 9.5.0.

For now, a workaround is put in place, but it is recommended that the WP `expectDeprecated()` method should be reevaluated in a future iteration.

Follow-up to [51559-51571].

Props jrf.
See #46149.
Built from https://develop.svn.wordpress.org/trunk@51572


git-svn-id: http://core.svn.wordpress.org/trunk@51183 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.9-alpha-51571';
+$wp_version = '5.9-alpha-51572';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.