autopkgtest now references ubuntu-server:live, the only ubuntu-server we still build.

debian/changelog

@@ -1,6 +1,8 @@
 livecd-rootfs (2.784) UNRELEASED; urgency=medium
 
   * Don't set a desktop base seed for ubuntu-base or ubuntu-core.
+  * autopkgtest now references ubuntu-server:live, the only ubuntu-server we
+    still build.
 
  -- Steve Langasek <steve.langasek@ubuntu.com>  Sun, 25 Sep 2022 01:40:22 -0700
 

debian/tests/default-bootstraps

@@ -37,7 +37,7 @@ ALL_TRIPLETS="
  ubuntu-mate-desktop::
  ubuntu-mate-live::
  ubuntu-netbook::
- ubuntu-server::
+ ubuntu-server:live:ubuntu-server
  xubuntu::"
 
 if [ -z "$SELECTED_TRIPLETS" ]; then