DEV: Allow writes to PG even if Redis is readonly mode.

Previously, I thought it was better to drop the site into reading mode
when Redis has failed over to the replica but it created more errors
while Redis is in readonly mode since ActiveRecord would prevent us from
writing to PG even though PG is up.

config/initializers/002-rails_failover.rb

@@ -55,16 +55,12 @@ if defined?(RailsFailover::ActiveRecord)
     Discourse.redis.exists?(
       Discourse::PG_READONLY_MODE_KEY,
       Discourse::PG_FORCE_READONLY_MODE_KEY
-    ) || (
-      GlobalSetting.redis_config[:replica_host] &&
-      Discourse.redis.connection[:host] == GlobalSetting.redis_config[:replica_host]
     )
   rescue => e
     if e.is_a?(Redis::CannotConnectError)
-      true
-    else
       Rails.logger.warn "#{e.class} #{e.message}: #{e.backtrace.join("\n")}"
+    end
+
     false
   end
 end
-end