Don't calculate push size for more changes if limit is already execeeded

ee/lib/ee/gitlab/git_access.rb

@@ -89,16 +89,16 @@ module EE
         # clear stale lock files.
         project.repository.clean_stale_repository_files
 
-        # rubocop: disable CodeReuse/ActiveRecord
-        push_size_in_bytes = changes_list.sum do |change|
-          repository.new_blobs(change[:newrev]).sum(&:size)
-        end
-        # rubocop: enable CodeReuse/ActiveRecord
+        push_size_in_bytes = 0
+
+        changes_list.each do |change|
+          push_size_in_bytes += repository.new_blobs(change[:newrev]).sum(&:size) # rubocop: disable CodeReuse/ActiveRecord
 
           if project.changes_will_exceed_size_limit?(push_size_in_bytes)
             raise ::Gitlab::GitAccess::UnauthorizedError, ::Gitlab::RepositorySizeError.new(project).new_changes_error
           end
         end
+      end
 
       def check_size_limit?
         strong_memoize(:check_size_limit) do