Overview

Add a PR check that coverage for the aws-cdk package (the CLI) must never decrease compared to main.

Background

The AWS CLI currently requires comparatively low coverage by tests:

statements: 60
branches: 45

The actual coverage is thankfully higher:

=============================== Coverage summary ===============================
Statements   : 81.59% ( 5462/6694 )
Branches     : 68.05% ( 1764/2592 )
Functions    : 84.49% ( 1128/1335 )
Lines        : 81.9% ( 5211/6362 )
================================================================================

However we should ideally have 90%+ on all these. In the meantime, add a PR check that coverage must never decrease.