move Retry code to its own method for Hooking purposes

[vivianlonging]

This pull request just moves the code that makes the Player retry to its own method.
I'm trying to introduce a code mechanic that revolves around whether or not the end user retries, and I cannot realistically hook into the source function for Retrying, so I made this pull request in the hopes that this can resolve my problem, and it appears to currently

[vivianlonging]

I also spoke with an Everest dev who says it might make the most sense to make it a function inside level, which would resolve this conflict more efficiently with a different PR

[CrackedP0t]

This seems totally reasonable - I'd be happy to merge this, if you remove the changes to the csproj. If you think it should be changed that's fine, but I think it should be in a different PR.

[vivianlonging]

I'm going to wait a few days to try to get a response as to whether or not Everest will definitely make the Retry method a method inside Level because that would be a bigger help in general