Update git submodules

* Update swift from branch 'master'
  to c7774d960c4186b166e95b1122b1652d090de64e
  - Merge "object-updater: defer ratelimited updates"
  - object-updater: defer ratelimited updates
    
    Previously, objects updates that could not be sent immediately due to
    per-container/bucket ratelimiting [1] would be skipped and re-tried
    during the next updater cycle. There could potentially be a period of
    time at the end of a cycle when the updater slept, having completed a
    sweep of the on-disk async pending files, despite having skipped
    updates during the cycle. Skipped updates would then be read from disk
    again during the next cycle.
    
    With this change the updater will defer skipped updates to an
    in-memory queue (up to a configurable maximum number) until the sweep
    of async pending files has completed, and then trickle out deferred
    updates until the cycle's interval expires. This increases the useful
    work done in the current cycle and reduces the amount of repeated disk
    IO during the next cycle.
    
    The deferrals queue is bounded in size and will evict least recently
    read updates in order to accept more recently read updates. This
    reduces the probablility that a deferred update has been made obsolete
    by newer on-disk async pending files while waiting in the deferrals
    queue.
    
    The deferrals queue is implemented as a collection of per-bucket
    queues so that updates can be drained from the queues in the order
    that buckets cease to be ratelimited.
    
    [1] Related-Change: Idef25cd6026b02c1b5c10a9816c8c6cbe505e7ed
    
    Co-Authored-By: Clay Gerrard <clay.gerrard@gmail.com>
    Co-Authored-By: Matthew Oliver <matt@oliver.net.au>
    Change-Id: I95e58df9f15c5f9d552b8f4c4989a474f52262f4

swift

@@ -1 +1 @@
-Subproject commit 16a3067746ef7766a0ae7a9edf84a9557297422a
+Subproject commit c7774d960c4186b166e95b1122b1652d090de64e