Fix FilePathField required argument

[radekwlsk]

Description

Following on the discussion in #8804 this PR fixes required argument lost in FilePathField constructor by making sure it is passed to the super().__init__ call with other keyword arguments.

[radekwlsk]

@auvipy Not sure what the CI error is. Seems that deprecation warnings are making it fail?

[auvipy]

can you please check why the CI is failing?? might be unrelated to this PR after checking the error message though

[auvipy]

I think we should get rid of python 3.6 now from CI

[radekwlsk]

@auvipy Also I wonder if setting allow_blank=False together with required=False should remove ("", "---------") from path choices. As currently django's FilePathField will add it whenever required=False and that will make "" a valid choice and skip allow_blank=False.

Not sure of the expected behaviour though, as it is based on ChoiceField and that does not support allow_blank, right?

[auvipy]

we should align with django mainly

[radekwlsk]

Waiting for CI fix on master.

[auvipy]

just pull from main branch