Add GTG integration tests to ensure compatibility with `measurement.php` updates

## Feature Description

The GTG `measurement.php` file is frequently updated. The surfaces in SK that integrate with `measurement.php` should have proper test coverage to ensure that SK is immune to changes in `measurement.php`.

---------------

_Do not alter or remove anything below. The following sections will be managed by moderators only._

## Acceptance criteria

*

## Implementation Brief

* [ ]

### Test Coverage

*

## QA Brief

*

## Changelog entry

*

Start by locating the SK surfaces that integrate with GTG's measurement.php and review any existing integration-test entry points. Define coverage for the affected surfaces, then verify the tests still pass when measurement.php changes so compatibility is protected.

Written by the indexing model from the issue text.