fix: package.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-ANGULAR-570058

package.json

@@ -4,7 +4,7 @@
     "description": "Angular service to use factory keyboard event",
     "main": "dist/angular-ys-service-keyboard.js",
     "dependencies": {
-        "angular": "~1.6.1",
+        "angular": "~1.8.0",
         "angular-ys-factory-keyboard": "~1.0.0",
         "jquery": "~3.2.0"
     },