Replace hardcoded version string + globs with build variables

[cgillum]

Resolves #212

This PR does two things:

• Removes the usage of version globs when referencing the WebJobs extension (see NU1605: Warning As Error: Detected package downgrade: Microsoft.Azure.WebJobs.Extensions.DurableTask from 2.13.2 to 2.13.1 #212).
• Removes the need to update hardcoded strings by putting this version configuration into the build.

Note that we're including this pas part of a 1.3.x release since only 1.2.x versions are affected by the version glob issue.