fix(package): update @angular/cdk to version 9.2.4

Closes #83

Author: greenkeeper[bot]

demo/package.json

@@ -27,7 +27,7 @@
   "private": true,
   "dependencies": {
     "@angular/animations": "^7.2.0",
-    "@angular/cdk": "^7.2.1",
+    "@angular/cdk": "^9.2.4",
     "@angular/common": "^7.2.0",
     "@angular/compiler": "^7.2.0",
     "@angular/core": "^7.2.0",