Add GitHub action to auto approve and merge security patches from dependabot

[ltrung]

Description of changes:
Add GitHub action to auto approve and merge security patches for minor and patch semver update from npm dependencies from dependabot following https://docs.github.com/en/code-security/dependabot/working-with-dependabot/automating-dependabot-with-github-actions

Testing:

Can these tested using a demo application? Please provide reproducible step-by-step instructions.
N/A

Checklist:

1. Have you successfully run npm run build:release locally? N/A

2. Do you add, modify, or delete public API definitions? If yes, has that been reviewed and approved? N/A

3. Do you change the wire protocol, e.g. the request method? If yes, has that been reviewed and approved? N/A

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[hensmi-amazon]

noice