clarified version: Apple now counts like 11, 12, ...;

--- a/src/Pure/Admin/isabelle_cronjob.scala	Sun Jul 04 18:35:57 2021 +0100
+++ b/src/Pure/Admin/isabelle_cronjob.scala	Tue Jul 06 12:36:47 2021 +0200
@@ -319,7 +319,7 @@
         options = "-m32 -B -M1,2,4 -e ISABELLE_GHC_SETUP=true -p pide_session=false",
         self_update = true, args = "-a -d '~~/src/Benchmarks'")),
       List(
-        Remote_Build("macOS 11.1 Big Sur", "mini1",
+        Remote_Build("macOS 11 Big Sur", "mini1",
           options = "-m32 -B -M1x2,2,4 -p pide_session=false" +
             " -e ISABELLE_OCAML=ocaml -e ISABELLE_OCAMLC=ocamlc -e ISABELLE_OCAML_SETUP=true" +
             " -e ISABELLE_GHC_SETUP=true" +