* Added guzzlehttp/guzzle 6.3.3.
==== Changed external libraries ====
+* Updated OOUI from v0.29.2 to v0.30.2.
* Updated wikimedia/xmp-reader from 0.6.0 to 0.6.1.
* Updated wikimedia/scoped-callback from 2.0.0 to 3.0.0.
* Updated wikimedia/ip-set from 1.2.0 to 2.0.0.