Use Redis SharedState instead of Cache

ee/lib/gitlab/geo/log_cursor/event_gap_tracking.rb

@@ -7,7 +7,7 @@ module Gitlab
         attr_reader :log_level
         attr_accessor :previous_id
 
-        GEO_LOG_CURSOR_GAPS = "Gitlab::Geo::LogCursor::Gaps".freeze
+        GEO_LOG_CURSOR_GAPS = 'geo:log_cursor:gaps'.freeze
         GAP_GRACE_PERIOD = 10.minutes
         GAP_OUTDATED_PERIOD = 1.hour
 
@@ -68,7 +68,7 @@ module Gitlab
         end
 
         def with_redis
-          ::Gitlab::Redis::Cache.with { |redis| yield redis }
+          ::Gitlab::Redis::SharedState.with { |redis| yield redis }
         end
 
         def grace_timestamp

ee/spec/lib/gitlab/geo/log_cursor/event_gap_tracking_spec.rb

@@ -137,7 +137,7 @@ describe Gitlab::Geo::LogCursor::EventGapTracking, :clean_gitlab_redis_cache do
   end
 
   def read_gaps
-    ::Gitlab::Redis::Cache.with do |redis|
+    ::Gitlab::Redis::SharedState.with do |redis|
       redis.zrangebyscore(described_class::GEO_LOG_CURSOR_GAPS, '-inf', '+inf', with_scores: true)
     end
   end