test: use vim.uv if available

Author: trimclain

tests/minimal_init.lua

@@ -9,7 +9,7 @@ end
 function M.load(plugin)
     local name = plugin:match(".*/(.*)")
     local package_root = M.root(".tests/site/pack/deps/start/")
-    if not vim.loop.fs_stat(package_root .. name) then
+    if not (vim.uv or vim.loop).fs_stat(package_root .. name) then
         print("Installing " .. plugin)
         vim.fn.mkdir(package_root, "p")
         vim.fn.system({