fix: frontend build warnings

docker/Dockerfile.frontend

@@ -8,6 +8,7 @@ WORKDIR /app
 COPY package.json package-lock.json ./
 RUN npm install
 COPY . .
+RUN npx browserslist@latest --update-db
 RUN npm run build
 
 # production stage

frontend/package.json

@@ -15,6 +15,7 @@
   "devDependencies": {
     "@vue/cli-service": "~5.0.0",
     "nodemon": "^2.0.19",
-    "vue-cli-plugin-vuestic-ui": "~1.0.8"
+    "vue-cli-plugin-vuestic-ui": "~1.0.8",
+    "@babel/core": "^7.0.0"
   }
-}
+}