chore(ci): check msrv

Author: tottoto

.github/workflows/CI.yml

@@ -32,6 +32,14 @@ jobs:
       - name: Run tests
         run: cargo test --workspace
 
+  msrv:
+    needs: [style]
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: taiki-e/install-action@cargo-hack
+      - run: cargo hack --rust-version --no-dev-deps check
+
   minimal-versions:
     needs: [style]
     runs-on: ubuntu-latest