Update git submodules

* Update docs/submodules/doctor from branch 'master'
  - Select stable/ocata packages

    It also protects if flask is already installed.

    Change-Id: Iec5d65fe307d702ec6f600333d6bc9cc3ab2ee33
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/doctor b/docs/submodules/doctor
index 7cbdc3b..dfb3c06 160000 (submodule)
--- a/docs/submodules/doctor
+++ b/docs/submodules/doctor
@@ -1 +1 @@
-Subproject commit 7cbdc3b64449c729c39dd33e1785076b8a127d68
+Subproject commit dfb3c066a1c325ba7ca028be98d9ec04af994f48