Bootstrap/Load: Add documentation warning about updating $table_prefix.

Props bjerke-johannessen, swissspidy, SergeyBiryukov, morganestes, stevenlinx, jorbin.
Fixes #34189.


git-svn-id: https://develop.svn.wordpress.org/trunk@59044 602fd350-edb4-49c9-b593-d223f7449a82

Author: aaronjorbin

wp-config-sample.php

@@ -64,6 +64,12 @@
  *
  * You can have multiple installations in one database if you give each
  * a unique prefix. Only numbers, letters, and underscores please!
+ *
+ * At the installation time, DB tables names with $table_prefix are created.
+ * Changing this value after WordPress is installed will make your site think
+ * it has not been installed.
+ *
+ * @link https://developer.wordpress.org/advanced-administration/wordpress/wp-config/#table-prefix
  */
 $table_prefix = 'wp_';