Adding SECURITY.md file for developers to report any security issues …

[anqi0103]

Description

Created a SECURITY.md file to guide users/contributors to report any security issue they found.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}