Update GitHub Actions

Signed-off-by: Sora Morimoto <[email protected]>

.github/dependabot.yml

@@ -0,0 +1,6 @@
+version: 2
+updates:
+  - package-ecosystem: github-actions
+    directory: /
+    schedule:
+      interval: weekly

.github/workflows/test.yml

@@ -9,16 +9,18 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ocaml-version: ["4.13.1", "4.12.1", "4.11.2"]
-        operating-system: [macos-latest, ubuntu-latest, windows-latest]
+        os: [macos-latest, ubuntu-latest, windows-latest]
+        ocaml-compiler: ["4.14", "4.13"]
 
-    runs-on: ${{ matrix.operating-system }}
+    runs-on: ${{ matrix.os }}
 
     steps:
-      - name: Checkout code
-        uses: actions/checkout@v2
+      - uses: actions/checkout@v4
 
-      - name: Use OCaml ${{ matrix.ocaml-version }}
-        uses: ocaml/setup-ocaml@v2
+      - uses: ocaml/setup-ocaml@v3
         with:
-          ocaml-compiler: ${{ matrix.ocaml-version }}
+          ocaml-compiler: ${{ matrix.ocaml-compiler }}
+
+      - run: opam exec -- dune build
+
+      - run: opam exec -- dune runtest