This changeset replaces `this.element._trigger('focus');` with `this.element.trigger('focus');` in `wpdialog` to fix a JS error introduced in [55052].
Indeed, `this` inside the `open()` function of `wpdialog` refers to the jQuery UI widget, whereas `this.element` is the jQuery object of the DOM element. Thus, native jQuery methods need to be used, as `_trigger` is only defined on the jQuery UI widget.
Follow-up to [55052].
Props TobiasBg, audrasjb, shubham1gupta.
Fixes#56830.
Built from https://develop.svn.wordpress.org/trunk@55134
git-svn-id: http://core.svn.wordpress.org/trunk@54667 1a063a9b-81f0-0310-95a4-ce76da25c4cd
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