gonzalezreal
Resolve many concurrency warnings
This is a first attempt to resolve many concurrency warnings in preparation for strict concurrency with Swift 6.0. It depends on the changes I made in NetworkImage here: https://github.com/gonzalezreal/NetworkImage/pull/33
I'm still unsure how to resolve the warnings related to the four instances of static var defaultValue, structs conforming to ImageProvider, and cmark in MarkdownParser.swift.
@MojtabaHs, @gonzalezreal has already said that he's working on his own solution for Swift 6 compatibility. However, I'm not sure how you would break this into separate commits. This PR is meant as a starting point, and perhaps it won't even be used in the end. You can do with it what you like.