chore: update security support versions

Author: cotes2020

.github/SECURITY.md

@@ -2,11 +2,12 @@
 
 ## Supported Versions
 
-| Version | Supported          |
-|---------| ------------------ |
-| 5.x     | :white_check_mark: |
-| < 5.0.0 | :x:                |
+| Version   | Supported |
+|:----------|:---------:|
+| `6.x`     |     ✓     |
+| < `6.0.0` |     ✗     |
 
 ## Reporting a Vulnerability
 
-If you find a vulnerability, please report it to `cotes.chung@gmail.com`. We will try our best to respond within a week. Thank you for your time!
+If you find a vulnerability, please report it to `cotes.chung@gmail.com`.
+We will try our best to respond within a week. Thank you for your time!