drop eol ubuntu releases lunar and mantic

lunar has a broken repository (missing repropro package on arm64) and
causing ci to fail

debian/.debian-ci.yml

@@ -168,11 +168,11 @@ default:
     SPECIAL: [ 'bpo12' ]
 
   - OS: ubuntu
-    SUITE: [ 'focal', 'jammy', 'lunar', 'mantic', 'noble', 'oracular' ]
+    SUITE: [ 'focal', 'jammy', 'noble', 'oracular' ]
     DOCKER_ARCH: amd64
     HOSTING_PROVIDER_TAG: tpa
   - OS: ubuntu
-    SUITE: [ 'focal', 'jammy', 'lunar', 'mantic', 'noble', 'oracular' ]
+    SUITE: [ 'focal', 'jammy', 'noble', 'oracular' ]
     DOCKER_ARCH: arm64
     HOSTING_PROVIDER_TAG: osuosl