Remove proxy_test (duplicates sudo_test)

tests/proxy_test.py

@@ -1,18 +0,0 @@
-import logging
-import os
-
-import mitogen.ssh
-import mitogen.sudo
-import mitogen.utils
-
-@mitogen.utils.run_with_router
-def main(router):
-    mitogen.utils.log_to_file(io=False)
-    child1 = router.ssh(name='u', hostname='u')
-    child2 = router.sudo(
-        username='sudo_pw_test',
-        password='x',
-        name='sudo_pw_test',
-        via=child1,
-    )
-    child2.call(os.system, 'id')