python-argcomplete: Add new package

From the README:

Argcomplete provides easy, extensible command line tab completion of
arguments for your Python application.

Signed-off-by: Jeffery To <jeffery.to@gmail.com>

lang/python/python-argcomplete/test.sh

@@ -0,0 +1,5 @@
+#!/bin/sh
+
+[ "$1" = python3-argcomplete ] || exit 0
+
+python3 -c 'import argcomplete'