Test property mapping fails for SCIM and LDAP mappings

## What

the admin “Test property mapping” action fails for SCIM/LDAP mappings (missing context / always errors) even when real sync works.

## Want

- The admin “Test property mapping” action fails for SCIM/LDAP mappings (missing context / always errors) even when real sync works

## Ideas this came from

- [#11294 Test Property Mapping for SCIM Source fails with "name 'data' is not defined"](https://github.com/goauthentik/authentik/issues/11294) — First of all, thank you for the fast fix of #11230, I retested the bug and it's definitely closed. Unfortunately I stumbled upon another bug, which I couldn't t
- [#12968 Test of LDAP Property Mappings fails every time](https://github.com/goauthentik/authentik/issues/12968) — Testing an LDAP property mapping doesn't work: To Reproduce Steps to reproduce the behavior: 1. Go to https://authentik.example.com/if/admin/#/core/property-map

Start with the admin “Test property mapping” action and reproduce the failure for both SCIM and LDAP mappings. Compare that path with a real sync, using issues #11294 and #12968 as context. Done means the action supplies the required context and succeeds for mappings that work during synchronization.

Written by the indexing model from the issue text.