Allow AssemblyCleanup and ClassCleanup methods to accept TestContext object

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Summary

Allow AssemblyCleanup and ClassCleanup methods to accept TestContext object.

Background and Motivation

By allowing [AssemblyCleanup] and [ClassCleanup] methods to accept a TestContext object as parameter (or not for backward compatibility), we would allow symetrical APIs and would unlock some new capabilities. For example, when using cooperative cancellation (or cooperative timeout) we need to have access to the CancellationToken object which is current impossible in the current shape.

Proposed Feature

Allow overload for the [AssemblyCleanup] and [ClassCleanup] method accepting a single parameter of type TestContext. The related analyzer and code-fix should be updated accordingly.