Description:
On BASE, even if you define a field as Non Required, when use it in a form, when you save it after the inputs you want, appers a error message saying the field ( wich is a NonRequired field) must have a input

Steps to Reproduce:
1. Create a DB with one field ""Non required"
2. Crete a form using fileds and the one NonRequired
3. Execute the form
4. Input values but nothing in the NonRequired field
5. A error messege appers saying you must inout anithing in that field left empty (still it is NonRequired)

Actual Results:
Error message

Expected Results:
Saves normaly as on older versions


Reproducible: Always


User Profile Reset: No



Additional Info:
[Information automatically included from LibreOffice]
Locale: pt
Module: OfficeDatabaseDocument
[Information guessed from browser]
OS: Windows (All)
OS is 64bit: no
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Versão: 6.1.3.2 (x64)
ID da versão: 86daf60bf00efa86ad547e59e09d6bb77c699acb
Processos do CPU: 4; SO: Windows 10.0; Gestão da interface: padrão; 
Configuração regional: pt-PT (pt_PT); Calc: group threaded