Remove failing unit test after [30090].

Fixes #30194.

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git-svn-id: http://core.svn.wordpress.org/trunk@30160 1a063a9b-81f0-0310-95a4-ce76da25c4cd
In `gallery_shortcode()`, when the `link` attribute is equal to `file`, make sure to pass `$attr` as the 6th (!) argument, not 5th, to `wp_get_attachment_link()`.

Props bradyvercher.
Fixes #27402.

Built from https://develop.svn.wordpress.org/trunk@30161


git-svn-id: http://core.svn.wordpress.org/trunk@30161 1a063a9b-81f0-0310-95a4-ce76da25c4cd
In `_wp_json_convert_string()`, when `$use_mb` is `false`, perhaps pass a variable that actually exists to `wp_check_invalid_utf8()`.

Introduced in [30055].
See #30224.

Built from https://develop.svn.wordpress.org/trunk@30162


git-svn-id: http://core.svn.wordpress.org/trunk@30162 1a063a9b-81f0-0310-95a4-ce76da25c4cd