Merge branch '64388-remove-unused-code' into 'master'

Remove unused method

Closes #64388

See merge request gitlab-org/gitlab-ce!30576

lib/gitlab/metrics/system.rb

@@ -63,10 +63,6 @@ module Gitlab
       def self.monotonic_time
         Process.clock_gettime(Process::CLOCK_MONOTONIC, :float_second)
       end
-
-      def self.clk_tck
-        @clk_tck ||= `getconf CLK_TCK`.to_i
-      end
     end
   end
 end