opsian FTBFS on OCaml 5.1+

Even when installing `runtime_event_tools`

Author: Leonidas-from-XIV

packages/opsian/opsian.0.1/opam

@@ -9,7 +9,7 @@ bug-reports: "https://github.com/Opsian/opsian-ocaml/issues"
 depends: [
   "dune" {>= "2.8"}
   ("ocaml" {>= "4.12.0" & < "5.0.0"} |
-   ("ocaml" {>= "5.0.0"} & "runtime_events_tools"))
+   ("ocaml" {>= "5.0.0" & < "5.1"} & "runtime_events_tools"))
   "conf-automake"
   "conf-perl"
   "conf-liblzma"