[Bug] Error when entering the diff view of an added/deleted change

[Fidelxyz]

When entering the diff view for an added or deleted files that one of the sides does not exist, it throws an error:

Error executing lua callback: ...ovim/0.11.6/share/nvim/runtime/lua/vim/func/_memoize.lua:75: invalid value (nil) at index 1 in table for 'concat'
stack traceback:
	[C]: in function '_hash'
	...ovim/0.11.6/share/nvim/runtime/lua/vim/func/_memoize.lua:75: in function 'get'
	/Users/fidel/.config/nvim/lua/config/autocmds.lua:52: in function </Users/fidel/.config/nvim/lua/config/autocmds.lua:49>
	[C]: in function '__newindex'
	...im/lazy/codediff.nvim/lua/codediff/core/virtual_file.lua:29: in function <...im/lazy/codediff.nvim/lua/codediff/core/virtual_file.lua:15>