Add lower bound on ocaml 4.08

Author: shonfeder

packages/CamelCase/CamelCase.0.2.0/opam

@@ -10,7 +10,7 @@ homepage: "https://github.com/atomicptr/CamelCase"
 doc: "https://github.com/atomicptr/CamelCase"
 bug-reports: "https://github.com/atomicptr/CamelCase/issues"
 depends: [
-  "ocaml"
+  "ocaml" {>= "4.08"}
   "dune" {>= "3.17"}
   "ocamlformat"
   "odoc" {with-doc}