GHA: upgrade to setup-ocaml@v3 and add OCaml 5.1, 5.2 and 5.3 to the …

…test matrix

.github/workflows/main.yml

@@ -14,15 +14,13 @@ jobs:
           - macos-latest
           - windows-latest
         ocaml-compiler:
-          - 4.12.x
-          - 4.13.x
-          - 4.14.x
-          - 5.00.x
-        exclude:
-          - os: windows-latest
-            ocaml-compiler: 5.00.x
-          - os: macos-latest
-            ocaml-compiler: 4.08.x
+          - "4.12"
+          - "4.13"
+          - "4.14"
+          - "5.0"
+          - "5.1"
+          - "5.2"
+          - "5.3"
 
     runs-on: ${{ matrix.os }}
 
@@ -31,7 +29,7 @@ jobs:
         uses: actions/checkout@v3
 
       - name: Use OCaml ${{ matrix.ocaml-compiler }}
-        uses: ocaml/setup-ocaml@v2
+        uses: ocaml/setup-ocaml@v3
         with:
           ocaml-compiler: ${{ matrix.ocaml-compiler }}