Merge pull request #591 from openedx/feanil/update_security_emails

docs: Update the security e-mail address.

Author: sarina

README.rst

@@ -66,7 +66,7 @@ The assigned maintainers for this component and other project details may be fou
 
 Reporting Security Issues
 -------------------------
-Please do not report security issues in public. Please email security@edx.org.
+Please do not report security issues in public. Please email security@openedx.org.
 
 Project Structure
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