Get pylint-2.6 to work under vpython3 on Windows.

This change fixes a minor issue in the pylint-2.6.bat wrapper
script and adds a missing dependency on colorama.

With these changes, it looks like pylint-2.6 will now work on Windows.

Bug: 1157676
Change-Id: Ic23fc4cd04bf464034bf5471856fdfb646f66a75
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/3018262
Reviewed-by: Robbie Iannucci <iannucci@chromium.org>
Commit-Queue: Dirk Pranke <dpranke@google.com>

pylint-2.6

@@ -38,6 +38,10 @@
 #   name: "infra/python/wheels/lazy-object-proxy/${vpython_platform}"
 #   version: "version:1.4.3"
 # >
+# wheel: <
+#   name: "infra/python/wheels/colorama-py3"
+#   version: "version:0.4.1"
+# >
 #
 # # Pylint extensions.
 #

pylint-2.6.bat

@@ -9,4 +9,4 @@ setlocal
 set PATH=%PATH%;%~dp0
 
 :: Defer control.
-vpython "%~dp0\pylint-2.6" %*
+vpython3 "%~dp0\pylint-2.6" %*