Update git submodules

* Update docs/submodules/doctor from branch 'master'
  - replace urllib2 with urllib.request for python3

    Change-Id: I68036c295689fae55125854074e3bc4d920fec06
    Signed-off-by: dongwenjuan <dong.wenjuan@zte.com.cn>

diff --git a/docs/submodules/doctor b/docs/submodules/doctor
index 9ae13f8..1bc6eb0 160000 (submodule)
--- a/docs/submodules/doctor
+++ b/docs/submodules/doctor
@@ -1 +1 @@
-Subproject commit 9ae13f88c29d7babea19fb65bef208e631a12be4
+Subproject commit 1bc6eb0e8f1ed1e20edcdd7362c23c8948ed3d77