CI: Update ocaml/setup-ocaml to v3

Author: Julow

Diff for: .github/workflows/build-linux.yml

@@ -29,7 +29,7 @@ jobs:
 
       # Setup
       - name: Setup OCaml ${{ matrix.ocaml-version }}
-        uses: ocaml/setup-ocaml@v2
+        uses: ocaml/setup-ocaml@v3
         with:
           ocaml-compiler: ${{ matrix.ocaml-compiler }}
 

Diff for: .github/workflows/build-mingw64.yml

@@ -37,7 +37,7 @@ jobs:
         with:
           ref: ${{ env.build_ref }}
 
-      - uses: ocaml/setup-ocaml@v2
+      - uses: ocaml/setup-ocaml@v3
         with:
           ocaml-compiler: 4.14.x
           opam-repositories: |

Diff for: .github/workflows/build-others.yml

@@ -30,7 +30,7 @@ jobs:
 
       # Setup
       - name: Setup OCaml ${{ matrix.ocaml-version }}
-        uses: ocaml/setup-ocaml@v2
+        uses: ocaml/setup-ocaml@v3
         with:
           ocaml-compiler: ${{ matrix.ocaml-compiler }}
           opam-repositories: |