[4.2] Create the field in the base model when it doesn't exist

[laoneo]

Summary of Changes

The database model has since #37095 a magic method to deliver the _dbo variable. This function needs to create the properties when they do not exist.

Testing Instructions

Edit a module in the back end.

Actual result BEFORE applying this Pull Request

The following error happens:
_Attempt to assign property "params" on null _

Expected result AFTER applying this Pull Request

Module form shows up.

[brianteeman]

and that's why I said low level changes like #37095 should have better testing instructions and automated tests

[brianteeman]

Confirming that it fixes the broken pr

Wondring why the url contains an empty clientid

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[brianteeman]

I have tested this item ✅ successfully on 8a2c824

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[laoneo]

The pr #37095 is actually shipped with unit tests and the base model is tested with almost every system test we have. For sure there are always edge cases where something can break. In this case it broke because a model has an undeclared variable which is bad coding practice and will produce an error in PHP 9, when the RFC passes https://wiki.php.net/rfc/undefined_property_error_promotion.

[alikon]

I have tested this item ✅ successfully on 8a2c824

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[alikon]

RTC

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[roland-d]

Thanks everybody