Update dependency karafka-testing to v2.5.4 (#609)

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

Author: renovate[bot]

v2.5-non-rails/Gemfile.lock

@@ -48,8 +48,8 @@ GEM
       logger
       mini_portile2 (~> 2.6)
       rake (> 12)
-    karafka-testing (2.5.3)
-      karafka (>= 2.5.0.beta1, < 2.6.0)
+    karafka-testing (2.5.4)
+      karafka (>= 2.5.0, < 2.6.0)
       waterdrop (>= 2.8.0)
     logger (1.7.0)
     mini_portile2 (2.8.9)

v2.5-rails/Gemfile.lock

@@ -134,8 +134,8 @@ GEM
       logger
       mini_portile2 (~> 2.6)
       rake (> 12)
-    karafka-testing (2.5.3)
-      karafka (>= 2.5.0.beta1, < 2.6.0)
+    karafka-testing (2.5.4)
+      karafka (>= 2.5.0, < 2.6.0)
       waterdrop (>= 2.8.0)
     karafka-web (0.11.3)
       erubi (~> 1.4)