Documentation Build Improvements

[paulirwin]

Is there an existing issue for this?

• I have searched the existing issues

Task description

Broken out from feedback on #961:

• Each build adds blank lines to the end of some files; ideally this would be idempotent and would not result in pending git changes.
• Investigate if we can read the target frameworks for each subsite from a common JSON location, or worst case set it in the powershell script