Tests: Revert [48973].

These tests ensure that a `_doing_it_wrong()` notice is thrown when `wpdb::prepare()` is called incorrectly, but also that the function will still handle the provided input as correctly as possible.

Disabling these tests on PHP 8 hides a problem, i.e. the function will no longer throw a notice and handle things correctly, it will now cause a white screen of death due to a fatal error.

That is a backward compatibility break, and `wpdb::prepare()` should be updated instead to maintain the original behaviour on PHP 8.

Props jrf, ayeshrajans.
See #50913, #50639.
Built from https://develop.svn.wordpress.org/trunk@48979


git-svn-id: http://core.svn.wordpress.org/trunk@48741 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.6-alpha-48978';
+$wp_version = '5.6-alpha-48979';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.