Silence load balancing from backtrace also for FOSS

When running specs with FOSS_ONLY=1 load balancing code re-appeared in
backtraces.

config/initializers/backtrace_silencers.rb

@@ -3,8 +3,8 @@
 Rails.backtrace_cleaner.remove_silencers!
 
 # This allows us to see the proper caller of SQL calls in {development,test}.log
-if (Rails.env.development? || Rails.env.test?) && Gitlab.ee?
-  Rails.backtrace_cleaner.add_silencer { |line| %r(^lib/gitlab/database/load_balancing).match?(line) }
+if Rails.env.development? || Rails.env.test?
+  Rails.backtrace_cleaner.add_silencer { |line| %r{^lib/gitlab/database/load_balancing}.match?(line) }
 end
 
 Rails.backtrace_cleaner.add_silencer { |line| !Gitlab::APP_DIRS_PATTERN.match?(line) }