Update chaos-studio-versions.md

Updated Ubuntu Linux versions we support

Author: nikhilkaul-msft

articles/chaos-studio/chaos-studio-versions.md

@@ -28,7 +28,7 @@ The Chaos Studio agent is tested for compatibility with the following operating
 | openSUSE Leap 15.2              | ✓ |   |
 | Debian 10 Buster                | ✓ | Installation of `unzip` utility required |
 | Oracle Linux 8.3                | ✓ |   |
-| Ubuntu Server 18.04 LTS         | ✓ |   |
+| Ubuntu Server 20.04/22.04 LTS         | ✓ |   |
 
 The agent isn't currently tested against custom Linux distributions or hardened Linux distributions (for example, FIPS or SELinux).