Bump actions/setup-node from 4 to 6

Bumps [actions/setup-node](https://github.com/actions/setup-node) from 4 to 6.
- [Release notes](https://github.com/actions/setup-node/releases)
- [Commits](https://github.com/actions/setup-node/compare/v4...v6)

---
updated-dependencies:
- dependency-name: actions/setup-node
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/main.yml

diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 966e338..73085d6 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -200,7 +200,7 @@
       # extra round for VSCodeExt which is built with 'release' config
       - name: Set up node
         if: ${{ (matrix.config == 'release') && success() }}
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@v6
         with:
           node-version: 20.18.1
 
@@ -231,7 +231,7 @@
           distribution: ${{ env.DEFAULT_JAVA_DISTRIBUTION }}
 
       - name: Set up node
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@v6
         with:
           node-version: 20.18.1