Adding Microsoft SECURITY.MD

[microsoft-github-policy-service[bot]]

Please accept this contribution adding the standard Microsoft SECURITY.MD :lock: file to help the community understand the security policy and how to safely report security issues. GitHub uses the presence of this file to light-up security reminders and a link to the file. This pull request commits the latest official SECURITY.MD file from https://github.com/microsoft/repo-templates/blob/main/shared/SECURITY.md.

Microsoft teams can learn more about this effort and share feedback within the open source guidance available internally.

[opbld30]

Learn Build status updates of commit 1ecb4ea:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
SECURITY.md	:white_check_mark:Succeeded

For more details, please refer to the build report.

Note: Broken links written as relative paths are included in the above build report. For broken links written as absolute paths or external URLs, see the broken link report.

For any questions, please:

• Try searching the learn.microsoft.com contributor guides
• Post your question in the Learn support channel