Update git submodules

* Update docs/submodules/doctor from branch 'master'
  - Merge "Fix links to remove references to submodules"
  - Fix links to remove references to submodules

    All references to submodules must be removed for docs to
    work going forward.

    Can be tested once your project has a local tox file

    Change-Id: I3f04ea564b98cc100ea1438f08b1afe3c4c4416d
    Signed-off-by: Aric Gardner <agardner@linuxfoundation.org>

diff --git a/docs/submodules/doctor b/docs/submodules/doctor
index 3ddc239..2d4a9f0 160000 (submodule)
--- a/docs/submodules/doctor
+++ b/docs/submodules/doctor
@@ -1 +1 @@
-Subproject commit 3ddc2392b0ed364eede49ff006d64df3ea456350
+Subproject commit 2d4a9f0c0a93797da6534583f6e74553a4b634be