Implement pipeline seeds size methods

app/models/ci/pipeline.rb

@@ -312,6 +312,10 @@ module Ci
       @stage_seeds ||= config_processor.stage_seeds(self)
     end
 
+    def seeds_size
+      @seeds_size ||= stage_seeds.sum(&:size)
+    end
+
     def has_kubernetes_active?
       project.kubernetes_service&.active?
     end

lib/gitlab/ci/stage/seed.rb

@@ -3,7 +3,9 @@ module Gitlab
     module Stage
       class Seed
         attr_reader :pipeline
+
         delegate :project, to: :pipeline
+        delegate :size, to: :@jobs
 
         def initialize(pipeline, stage, jobs)
           @pipeline = pipeline