Fix go version of workflow

Author: Takuya Ueda

.github/workflows/testandvet.yml

@@ -25,11 +25,13 @@ jobs:
 
     - name: Checkout code
       uses: actions/checkout@v4.2.2
+      id: toolchain # see: https://github.com/actions/setup-go/issues/457#issuecomment-2480536859
+        run: echo "version=$(sed -ne '/^toolchain /s/^toolchain go//p' go.mod)" >> "$GITHUB_OUTPUT"
 
     - name: Install Go
       uses: actions/setup-go@v5.3.0
       with:
-        go-version-file: 'go.mod'
+        go-version: ${{ steps.toolchain.outputs.version }}
 
     - name: Cache Go module and build cache
       uses: actions/cache@v4.2.2