add: project trace tasks count

db/migrate/20220511022334_add_tasks_count_to_trace_users.rb

@@ -1,5 +0,0 @@
-class AddTasksCountToTraceUsers < ActiveRecord::Migration[5.2]
-  def change
-    add_column :trace_users, :tasks_count, :integer, default: 0
-  end
-end

db/migrate/20220511031711_add_trace_tasks_count_to_projects.rb

@@ -0,0 +1,5 @@
+class AddTraceTasksCountToProjects < ActiveRecord::Migration[5.2]
+  def change
+    add_column :projects, :trace_tasks_count, :integer, default: 0
+  end
+end