Improve performance of Rails backtrace cleaner configuration

Prefer Regexp#match?(String) over String#=~(Regexp).

changelogs/unreleased/pl-perf-backtrace-silencer.yml

+---
+title: Improve performance of Rails backtrace cleaner configuration
+merge_request: 40182
+author:
+type: performance

config/initializers/backtrace_silencers.rb

@@ -2,7 +2,7 @@ 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| line =~ %r(^ee/lib/gitlab/database/load_balancing) }
+  Rails.backtrace_cleaner.add_silencer { |line| %r(^ee/lib/gitlab/database/load_balancing).match?(line) }
 end
 
-Rails.backtrace_cleaner.add_silencer { |line| line !~ Gitlab::APP_DIRS_PATTERN }
+Rails.backtrace_cleaner.add_silencer { |line| !Gitlab::APP_DIRS_PATTERN.match?(line) }