Summary:
Followup to fe80a0c01d. Use a Markdown extension to let GitHub know this can be rendered as a Preview, otherwise GitHub will display the plaintext version.
[General] [Fixed] - Use Markdown in SUPPORT file
Pull Request resolved: https://github.com/facebook/react-native/pull/23791
Differential Revision: D14349422
Pulled By: hramos
fbshipit-source-id: 836746f35c6e962f3ca64a138bbf764529a6e043