FIX Add protection against deprecated warning from mb_check_encoding()

[edwilde]

Description

When the $fieldValue is not set, the mb_check_encoding() function raises a deprecation warning.

[Deprecated] mb_check_encoding(): Calling mb_check_encoding() without argument is deprecated

So we make sure the field value is set before using it.

Manual testing steps

Use the restful server to output a field which is not set

Issues

• Calling mb_check_encoding() without argument is deprecated PHP 8.2 #123

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[emteknetnz]

Please target 3.0 so that it can be patched released. You may need to rebase after doing that

[edwilde]

All set 🚀

...also noticed that CI is not testing in PHP 8.3, that expected?

[emteknetnz]

Hmm strange it's not testing in PHP 8.3 on pull-requests. It is testing 8.3 on the regular CI build, so on the very low chance there is an issue it'll be picked up within the next week or so.

[emteknetnz]

Linked PR has been merged, it will be automatically released shortly