chore: merge changes from digitialocean's image-check script

This includes changes up to May 2, 2024 from this link: https://github.com/digitalocean/marketplace-partners/commits/master/scripts/99-img-check.sh

contrib/images/digitalocean/in_parts/100-image-check

@@ -513,6 +513,9 @@ elif [[ "$OS" =~ Debian.* ]]; then
     11)
       osv=1
       ;;
+    12)
+      osv=1
+      ;;
     *)
       osv=2
       ;;
@@ -538,7 +541,7 @@ elif [[ $OS == "CentOS Stream" ]]; then
   fi
 elif [[ $OS == "Rocky Linux" ]]; then
   ost=1
-  if [[ $VER =~ 8\. ]]; then
+  if [[ $VER =~ 8\. ]] || [[ $VER =~ 9\. ]]; then
     osv=1
   else
     osv=2