chore(deps): update actions/setup-node action to v6 (#11)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
Co-authored-by: Martin Adámek <banan23@gmail.com>

Author: renovate[bot]

.github/workflows/ci.yml

@@ -13,7 +13,7 @@ jobs:
         node-version: [22, 24]
     steps:
       - uses: actions/checkout@v6
-      - uses: actions/setup-node@v4
+      - uses: actions/setup-node@v6
         with:
           node-version: ${{ matrix.node-version }}
           cache: npm