pylint-1.6: drop unused version

I can't see any users of this version via cs/, so drop it to speed up
the ensure_bootstrap phase.

Change-Id: I3779228daec2858d48c288023ffdb924b5038297
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/3245745Reviewed-by: Josip Sokcevic <sokcevic@google.com>
Commit-Queue: Mike Frysinger <vapier@chromium.org>

pylint-1.6

-#!/usr/bin/env vpython
-# Copyright 2019 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# Note: We use tags here instead of refs because refs will always hit the
-# network to see if there are any updates.
-
-# [VPYTHON:BEGIN]
-# # Third party dependencies.  These are only listed because pylint itself needs
-# # them.  Feel free to add/remove anything here.
-#
-# wheel: <
-#   name: "infra/python/wheels/configparser-py2_py3"
-#   version: "version:3.5.0"
-# >
-# wheel: <
-#   name: "infra/python/wheels/futures-py2_py3"
-#   version: "version:3.1.1"
-# >
-# wheel: <
-#   name: "infra/python/wheels/isort-py2_py3"
-#   version: "version:4.3.4"
-# >
-# wheel: <
-#   name: "infra/python/wheels/wrapt/${vpython_platform}"
-#   version: "version:1.10.11"
-# >
-# wheel: <
-#   name: "infra/python/wheels/backports_functools_lru_cache-py2_py3"
-#   version: "version:1.5"
-# >
-# wheel: <
-#   name: "infra/python/wheels/lazy-object-proxy/${vpython_platform}"
-#   version: "version:1.3.1"
-# >
-# wheel: <
-#   name: "infra/python/wheels/singledispatch-py2_py3"
-#   version: "version:3.4.0.3"
-# >
-# wheel: <
-#   name: "infra/python/wheels/enum34-py2"
-#   version: "version:1.1.6"
-# >
-# wheel: <
-#   name: "infra/python/wheels/mccabe-py2_py3"
-#   version: "version:0.6.1"
-# >
-# wheel: <
-#   name: "infra/python/wheels/six-py2_py3"
-#   version: "version:1.15.0"
-# >
-#
-# # Pylint extensions.
-#
-# wheel: <
-#   name: "infra/python/wheels/pylint-quotes-py2_py3"
-#   version: "version:0.1.8"
-# >
-#
-# # Pylint dependencies.
-#
-# wheel: <
-#   name: "infra/python/wheels/astroid-py2_py3"
-#   version: "version:1.4.9"
-# >
-#
-# wheel: <
-#   name: "infra/python/wheels/pylint-py2_py3"
-#   version: "version:1.6.5"
-# >
-# [VPYTHON:END]
-
-import sys
-
-import pylint_main
-
-sys.exit(pylint_main.main(sys.argv[1:]))