Fix wp support changelog

Author: sirreal

html-api-debugger/readme.txt

@@ -16,7 +16,7 @@ Please file issues and pull requests on the [GitHub repository](https://github.c
 == Changelog ==
 
 = 2.2 =
-* Drop support for WordPress 6.7.
+* Drop support for WordPress 6.6.
 * Drop basic fragment parsing and quirks mode support.
 * Add advanced context and fragment parsing when supported (WordPress 6.8+).
 * Add functionality to copy textual representations of the generated trees.