Refactoring: Use Paths.get() to avoid concatenation with File.separator

[stokito]

loadFormFieldRegistryEntries(): use try with close

[Flowdalic]

Thanks for your contribution. Could you elaborate on the motivation for this change?

[stokito]

This is more a code style and modernization type of change.
The Paths.get() makes the concatenation with the File.separator and makes code shorter and more stable. In many API places now used the Path instead of a string.
As a downside it may work slower in some places.