Merge branch 'stable-2.15'

* stable-2.15:
  AbstractElasticIndex: fix index name of delete request and add coverage
  Bazel: Remove unused commons-lang3
  DropWizardMetricMaker: Move sanitizeMetricName to MetricMaker base class
  Update git submodules
  Update git submodules
  Update git submodules
  AsciiDoctor: Format with google-java-format version 1.6
  Enable metrics for core queues
  WorkQueue: Add possibility to enable metrics

Change I7af2f9f6c ("Bazel: Remove unused commons-lang3") is reverted by
this merge since commons-lang3 is actually still used on master.

This reverts commit 51c938d39c5933f6f9e717f260a3f25303398f00.

Change-Id: I5ea8c03d27e7eaefd0067658b25d1c08efdfd0f4