Create SECURITY.md (#2071)

* Create SECURITY.md

A simple instruction for security researchers.

* update text security.md file

* Update SECURITY.md

Co-authored-by: Ahmed Galad's <36524318+glimz@users.noreply.github.com>

SECURITY.md

@@ -0,0 +1,7 @@
+# Security Policy
+
+## Reporting a Vulnerability
+
+Please report (suspected) security vulnerabilities to support@limesurvey.org or create a bug report and mark it as private. Marking it as private will make the bug report visible to only users who have access.
+
+You will receive a response from us within 48 hours. If the issue is confirmed, we will release a patch as soon as possible depending on complexity but historically within a few days.