Extend and fix zipfile (#10861)

* Add `CompleteDirs` and `FastLookup` (Python 3.8+).
* Add `Path.root` (Python 3.8+).
* Use concrete signature for `Path.open()` (Python 3.8).
* Fix signature of `Path.open()` for Python 3.9+:
   + Add overloads for text and binary modes with fixed return types.
   + Disallow extra arguments for binary modes.
   + Replace `*args` and `**kwargs` with accepted arguments for
     text modes.

Closes: #10847

tests/stubtest_allowlists/py38.txt

@@ -144,6 +144,9 @@ types.WrapperDescriptorType.__get__
 .*.__buffer__
 .*.__release_buffer__
 
+# A property at runtime that works like a method.
+zipfile.Path.open
+
 # Removed in 3.12
 distutils\..*
 asyncore.dispatcher.addr