Update src/state/opamFormatUpgrade.ml

Author: kit-ty-kate

src/state/opamFormatUpgrade.ml

@@ -1081,7 +1081,8 @@ let from_2_0_to_v2_1 _ conf =
      See https://github.com/ocurrent/ocaml-dockerfile/pull/92 *)
   let info_jobs_changed ~prev_jobs =
     OpamConsole.note
-      "The 'jobs' option was reset, its value was %d. \
+      "The 'jobs' option was reset, its value was %d and its new value \
+      will vary according to the current number of cores on your machine. \
        If it really was intended, you can set it again using:\n    \
        opam option jobs=%d --global" prev_jobs prev_jobs;
   in