Add required GA custom dimensions for a survey when using Reader Revenue Manager

## Feature Description

For users that may wish to avail of a survey in Reader Revenue Manager, in order to view results from the survey, the following custom dimensions are required in GA:
`survey_question`
`survey_answer`

Consider adding these via Site Kit when setting up Reader Revenue Manager, possibly even if Google Analytics is not connected via Site Kit. More details on these dimensions found [here](https://support.google.com/news/publisher-center/answer/12813936?sjid=13701662678752193909-EU#zippy=%2Ccollect-first-party-data-using-surveys).

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## Acceptance criteria

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## Implementation Brief

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### Test Coverage

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## QA Brief

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## Changelog entry

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No files, tests, or entry points are identified. Start by tracing the Reader Revenue Manager setup and how Site Kit configures Google Analytics custom dimensions; confirm the behavior when Analytics is not connected, and consider the work done when both survey dimensions are available for survey reporting.

Written by the indexing model from the issue text.