style: fix few stylings issue

Author: kiaking

src/module/module-collection.js

@@ -60,7 +60,6 @@ export default class ModuleCollection {
 
     return parent.hasChild(key)
   }
-
 }
 
 function update (path, targetModule, newModule) {

test/unit/modules.spec.js

@@ -80,12 +80,11 @@ describe('Modules', () => {
       store.commit('a/foo')
       expect(mutationSpy).toHaveBeenCalled()
     })
+
     it('dynamic module existance test', () => {
-      const store = new Vuex.Store({
-      })
+      const store = new Vuex.Store({})
 
-      store.registerModule('bonjour', {
-      })
+      store.registerModule('bonjour', {})
 
       expect(store.hasModule('bonjour')).toBe(true)
       store.unregisterModule('bonjour')