Update dependency karafka to v2.4.15 (#525)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

v2.4-rails/Gemfile.lock

@@ -98,7 +98,7 @@ GEM
     irb (1.14.1)
       rdoc (>= 4.0.0)
       reline (>= 0.4.2)
-    karafka (2.4.14)
+    karafka (2.4.15)
       base64 (~> 0.2)
       karafka-core (>= 2.4.4, < 2.5.0)
       karafka-rdkafka (>= 0.17.2)