[SanitizingFunctions|EscapingFunctions]Trait: add wp_kses_one_attr() to function lists

This function was introduced in WP 4.2.3.

I've done a cursory look-over of the code, but I have not gone down the rabbit-hole of examining all functions involved (and yes, `wp_kses_one_attr()` calls a _lot_ of functions under the hood).

Having said that, anastis did do a more detailed analysis and included their write-up of it in the ticket, so I'm satisfied that this function can be added to the list.

Based on this write-up, I believe the function should be added to both the `$sanitizingFunctions` list as well as the `$escapingFunctions` list.

Refs:
* https://developer.wordpress.org/reference/functions/wp_kses_one_attr/
* WordPress/WordPress-Coding-Standards 1765#issuecomment-512192213

Fixes 1765

Author: jrfnl

WordPress/Helpers/EscapingFunctionsTrait.php

@@ -92,6 +92,7 @@ trait EscapingFunctionsTrait {
 		'wp_json_encode'             => true,
 		'wp_kses_allowed_html'       => true,
 		'wp_kses_data'               => true,
+		'wp_kses_one_attr'           => true,
 		'wp_kses_post'               => true,
 		'wp_kses'                    => true,
 	);

WordPress/Helpers/SanitizingFunctionsTrait.php

@@ -96,6 +96,7 @@ trait SanitizingFunctionsTrait {
 		'wp_handle_upload'           => true,
 		'wp_kses_allowed_html'       => true,
 		'wp_kses_data'               => true,
+		'wp_kses_one_attr'           => true,
 		'wp_kses_post'               => true,
 		'wp_kses'                    => true,
 		'wp_parse_id_list'           => true,