remove vue-popperjs

package.json

@@ -25,7 +25,6 @@
     "localforage": "^1.5.0",
     "object-path": "^0.11.3",
     "phoenix": "^1.3.0",
-    "popper.js": "^1.14.7",
     "portal-vue": "^2.1.4",
     "sanitize-html": "^1.13.0",
     "v-click-outside": "^2.1.1",
@@ -33,7 +32,6 @@
     "vue": "^2.5.13",
     "vue-chat-scroll": "^1.2.1",
     "vue-i18n": "^7.3.2",
-    "vue-popperjs": "^2.0.3",
     "vue-router": "^3.0.1",
     "vue-template-compiler": "^2.3.4",
     "vuelidate": "^0.7.4",