chore(docs): Update SECURITY.md to reflect supported versions (#37264)

Update SECURITY.md

Author: mlgualtieri

Diff for: SECURITY.md

@@ -6,8 +6,9 @@ The following versions are currently being supported with security updates.
 
 | Version | Supported          |
 | ------- | ------------------ |
+| 5.x     | :heavy_check_mark: |
 | 4.x     | :heavy_check_mark: |
-| 3.x     | :heavy_check_mark: |
+| 3.x     | :x:                |
 | 2.x     | :x:                |
 | 1.x     | :x:                |
 | < 1.0   | :x:                |