Module Metatags field "robots" not handled correctly

Problem/Motivation

(At least) Using PHP 8.1 the field "robots" coming from the metatags contrib module is incorrectly handled as a string but it is an array

An error is logged in watchdog: TypeError: strip_tags(): Argument #1 ($string) must be of type string, array given in strip_tags() (line 977 of /var/domains/clipboard-baaz.nl/public_html/sites/all/modules/webtexttool/webtexttool.node.inc).

Steps to reproduce

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes