chore: release 2.1.2 (#258)

* updated CHANGELOG.md

* updated package.json

* updated samples/package.json

Author: yoshi-automation

video-intelligence/package.json

@@ -15,7 +15,7 @@
     "test": "mocha system-test --timeout=800000"
   },
   "dependencies": {
-    "@google-cloud/video-intelligence": "^2.1.1",
+    "@google-cloud/video-intelligence": "^2.1.2",
     "yargs": "^13.0.0"
   },
   "devDependencies": {