ajax `wp_ajax_update_plugin` show download failed when contain another update (eg: translations) with same process fail.

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I found that wp_ajax_update_plugin contain invalid response when trying to update plugin via ajax request.

This happend when $upgrader->bulk_upgrade( array( $plugin ) ); called, and any other update progress run on same time.

Eg: there are translations update exists and when contain errors on translations update, the plugin update tell that the plugin fail to download, but the plugins successfully updated.

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src/wp-admin/includes/ajax-actions.php

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Response WP_Ajax_Upgrader_Skin

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fix 55089.patch indentation