Upgraded Billboard.js to @1.8.0

Author: gunaseelann

package.json

@@ -14,7 +14,7 @@
   },
   "dependencies": {
     "axios": "^0.18.0",
-    "billboard.js": "^1.7.1",
+    "billboard.js": "^1.8.0",
     "bootstrap": "4.2.1",
     "bootstrap-vue": "^2.0.0-rc.11",
     "codemirror": "5.42.2",