#557 Implement working functionality for the DELETE /program/:programAssessmentId route

Proposed changes

This pull request resolves #557 by implementing the DELETE /program/:programAssessmentId route.

The DELETE /program/:programAssessmentId route deletes an existing program assessment in the database.

Tests for the DELETE /program/:programAssessmentId route and the service file functions have been completed and are included in the pull request.

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