[BUG] Map Classifications should only be visible when saved

[dvdl16]

Current Behavior

On Value-added Tax Return Settings, the 'Map Classifications' section is shown when the doc is not saved yet. This causes errors with the Link field lookups that are dependent on prior fields

Steps To Reproduce

1. Go to Value-added Tax Return Settings
2. Create a new record
3. See the issue on the dropdown fields under 'Map Classifications'

Expected Behavior

The 'Map Classifications' section should be hidden until a ' Transaction Classification Method ' is selected

Anything else?

No response

Environment and Versions

South Africa Customisations: v0.1.0
ERPNext: v15.17.1
Frappe Framework: v15.17.3
Frappe HR: v15.14.0

Operating System

Windows

What browsers are you seeing the problem on?

Firefox