fix: PHP Warning: Invalid argument supplied for foreach() in RockMigr…

[gebeer]

…ations.module.php:3510

Hi, When exporting field data with getConfig(), it sometimes contains 'template_ids' => '', This threw a Warning because the foreach cannot loop through an empty string. Also checking for $val avoids this.

[gebeer]

Didn't pay attention, so the PR wants to merge into main. You might want to merge this into dev instead. At least that was my intention :-)

[BernhardBaumrock]

I'll make that change manually, thank you very much for the fix :)