Add ReenterAfter override

[woksin]

Description

Adds an overload to ReenterAfter that takes in a Task<T> with a result and a Action callback that takes in that Task<T>.

Purpose

This pull request is a:

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist

• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)