ci: test OCaml 5.1.1

Author: favonia

.github/workflows/ocaml.yaml

@@ -10,7 +10,7 @@ jobs:
       matrix:
         include:
           - ocaml-compiler: "ocaml-base-compiler.5.0.0"
-          - ocaml-compiler: "ocaml-base-compiler.5.1.0"
+          - ocaml-compiler: "ocaml-base-compiler.5.1.1"
             with-doc: true
     runs-on: ubuntu-latest
     steps: