Installing Everest to a drive with a filesystem that does not support symlinks fails on Linux #1151

My mods and Everest install are up to date

Yes

I have recreated the bug with only Everest OR a minimum number of mods enabled

Yes

Describe the bug

As described in the title, when the user attempts to install Everest to an external drive with a filesystem that does not support symlinks (the example I ran into was exFAT) on Linux, MiniInstaller crashes when trying to symlink the Content/ folder.

Steps to reproduce

1. Install Celeste to a drive with a filesystem like exFAT, FAT32, etc
2. Install Everest to it
3. explode

Expected behavior

MiniInstaller should fall back to making a copy of the Content folder, just like Windows does.

Operating System

Arch Linux

Everest Version

6418

Mods required to reproduce

No response

Additional context

Relevant log-sharp.txt snippet:

Applying patch vanilla libraries
System.UnauthorizedAccessException: Access to the path '/run/media/.../Celeste/orig/Content' is denied.
--> System.IO.IOException: Operation not permitted
--- End of inner exception stack trace ---
   at Interop.ThrowExceptionForIoErrno(ErrorInfo errorInfo, String path, Boolean isDirError)
   at Interop.CheckIo(Int64 result, String path, Boolean isDirError)
   at System.IO.Directory.CreateSymbolicLink(String path, String pathToTarget)
   at MiniInstaller.BackUp.CreateBackupSymlinks() in MiniInstaller/BackUp.cs:line 86
   at MiniInstaller.BackUp.Backup() in MiniInstaller/BackUp.cs:line 73
   at MiniInstaller.Program.StandardMode(String[] args) in MiniInstaller/Program.cs:line 67

The exception is caught but is rethrown if the OS is not Windows: