Call vim.uv.realpath on path returned from jj root

On windows, jj root may return a UNC path. In these cases plenary Job
does not always succeed at finding the directory and returns an error.
To prevent this we call `vim.uv.realpath` so to canacolize the path so
that it is valid for neovim to use.

lua/telescope-jj/utils.lua

@@ -6,7 +6,8 @@ local putils = require("telescope.previewers.utils")
 local get_jj_root = function()
     local root, ret = ts_utils.get_os_command_output({ "jj", "root" })
     if ret == 0 then
-        return root[1]
+        local path = vim.uv.fs_realpath(root[1])
+        return path
     end
 
     error("jj root not found")