Workaround for setup-ocaml issue with self-hosted runner

Author: cknitt

.github/workflows/ci.yml

@@ -142,15 +142,25 @@ jobs:
           chmod +x _build/install/default/bin/*
 
       - name: Use OCaml ${{matrix.ocaml_compiler}}
-        uses: ocaml/[email protected]
-        if: matrix.os != 'windows-latest'
+        uses: ocaml/setup-ocaml@v2
+        if: matrix.os != 'macos-arm' && matrix.os != 'windows-latest'
+        with:
+          ocaml-compiler: ${{matrix.ocaml_compiler}}
+          opam-pin: false
+          opam-depext: false
+
+      - name: Use OCaml ${{matrix.ocaml_compiler}}
+        uses: ocaml/setup-ocaml@v2
+        env:
+          GITHUB_ACTIONS: false # see https://github.com/ocaml/setup-ocaml/issues/735#issuecomment-1845210572
+        if: matrix.os == 'macos-arm'
         with:
           ocaml-compiler: ${{matrix.ocaml_compiler}}
           opam-pin: false
           opam-depext: false
 
       - name: Use OCaml ${{matrix.ocaml_compiler}} (Win)
-        uses: ocaml/setup-ocaml@v2.1.7
+        uses: ocaml/setup-ocaml@v2
         if: matrix.os == 'windows-latest'
         with:
           ocaml-compiler: ${{matrix.ocaml_compiler}}