Update git submodules

* Update extensions/WikimediaEvents from branch 'wmf/1.30.0-wmf.17'
  - Encode human search relevance survey into html output

    Moves the search relevance configuration from javascript into php
    configuration so it can be run on a larger number of pages without
    exploding the size of javascript delivered to everyone with all
    that config.

    The downside of this approach is that because the config is cached
    into the page html any updates have to work their way through varnish
    caching. For the initial test this should be fine as we can purge the
    relevant pages over some small time period. In the future when we are
    doing larger scale collection we just have to keep in mind that
    configuration changes take around 7 days to propogate.

    Bug: T174387
    Change-Id: I7ae522155e67610d25b5857d7b3918559bce8bc7
    (cherry picked from commit e722fe1a9b0d41c3597f9f9326e7fc6f0e1cd9c6)

diff --git a/extensions/WikimediaEvents b/extensions/WikimediaEvents
index e1bc3bb..2b7e260 160000 (submodule)
--- a/extensions/WikimediaEvents
+++ b/extensions/WikimediaEvents
@@ -1 +1 @@
-Subproject commit e1bc3bbafeff9388c5d9c52a5abb0db1a638d1a9
+Subproject commit 2b7e260508374795880317807579fd2346c364a7