[Bug]: JSON Input - unable to select fields for parameters in Hop GUI

### Apache Hop version?

2.9.0, 2.10.0

### Java version?

17.0.2

### Operating system

Linux

### What happened?

The parameters section in the JSON Input transform can't load into the combobox the fields from the previous transform, despite being correctly linked.

Partial workaround: press the Get Fields button and remove the unnecessary fields. However, you can still face something similar to #3801: but in this case you may have to retype the field name since it's not selectable from the combobox...

### Issue Priority

Priority: 3

### Issue Component

Component: Hop Gui, Component: Transforms

Start by reproducing the JSON Input transform issue in Hop GUI 2.9.0 or 2.10.0 on Linux with Java 17.0.2, using a preceding linked transform and the Parameters section. Inspect how the field combobox is populated and verify that fields from the previous transform can be selected without using Get Fields or retyping names.

Written by the indexing model from the issue text.