Add ability to track number of records deviation and report it as warnings in email notifications

## Background
This can help tracking when ingested data is not complete.

## Feature
Add ability to track number of records deviation and report it as warnings in email notifications.

## Example [Optional]
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## Proposed Solution [Optional]
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No files, tests, or entry points are named. Start by locating the ingestion completeness checks and email notification path, then clarify how record deviation is measured and what warning output is expected. Done means deviations are tracked and corresponding warnings appear in email notifications.

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