Update git submodules

* Update docs/submodules/snaps from branch 'master'
  - Merge "Remove conditional on external_fixed_ips to allow for case that it is not set but network_id is set in external_gateway_info"
  - Remove conditional on external_fixed_ips to allow for case that
    it is not set but network_id is set in external_gateway_info

    Change-Id: Ib0fdfbf49730ca68d7c1d47c18c2ac17be637380
    Signed-off-by: Stuart Mackie <wsmackie@juniper.net>

diff --git a/docs/submodules/snaps b/docs/submodules/snaps
index b690666..f5ff39b 160000 (submodule)
--- a/docs/submodules/snaps
+++ b/docs/submodules/snaps
@@ -1 +1 @@
-Subproject commit b6906661c0c853761a4d65a5980e6f4f24194217
+Subproject commit f5ff39bd0b32c5d3c31bc21cb1f560161c559894