[TargetIntegrator] Dont run migrations in the specs

spec/unit/installer/user_project_integrator/target_integrator_spec.rb

@@ -24,6 +24,9 @@ module Pod
         @pod_bundle.xcconfigs['Debug'] = configuration
         @pod_bundle.xcconfigs['Release'] = configuration
         @target_integrator = TargetIntegrator.new(@pod_bundle)
+        @target_integrator.private_methods.grep(/^update_to_cocoapods_/).each do |method|
+          @target_integrator.stubs(method)
+        end
       end
 
       describe '#integrate!' do