新增：删除项目须同时删除所有的统计数据

app/models/project.rb

@@ -136,6 +136,7 @@ class Project < ApplicationRecord
   has_many :project_topic_ralates, dependent: :destroy 
   has_many :project_topics, through: :project_topic_ralates
   has_many :commit_logs, dependent: :destroy
+  has_many :daily_project_statistics, dependent: :destroy
   after_create :incre_user_statistic, :incre_platform_statistic
   after_save :check_project_members
   before_save :set_invite_code, :reset_unmember_followed, :set_recommend_and_is_pinned, :reset_cache_data