Refine release notes description design language to communicate when no release notes within top level Updates view

[mechamegane]

Problem: #96 adds a much desired feature! However, if there's no release notes, this isn't communicated out currently which means if a user has 20 apps being updated, and none of them have release notes it results in time and 40 clicks (one to open, one to "Close >" that result in no value.

Solution: I would suggest refining how it communicates out if there's release notes. For example, if "No description available." then do something like:

• Don't show the info button

or

• Use some two colors derived from the themes for the button to communicate if it does or doesn't have release notes that warrant clicking the button. For example the active window color could be used to indicate it has release notes

The first option seems like the most straightforward communication to user: no info button means no info provided by the app developer. However, that is my personal take