Update cucumber to v6 (webdriverio#5003)

Author: christian-bromann

packages/wdio-cucumber-framework/package.json

@@ -32,7 +32,7 @@
  "dependencies": {
  "@wdio/logger": "6.0.0-alpha.0",
  "@wdio/utils": "6.0.0-alpha.1",
- "cucumber": "^5.1.0",
+ "cucumber": "^6.0.5",
  "glob": "^7.1.2",
  "is-glob": "^4.0.0",
  "mockery": "~2.1.0"