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](actions/setup-node@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] <[email protected]>

Author: dependabot[bot]

.github/workflows/solana-native.yml

@@ -104,7 +104,7 @@ jobs:
     steps:
       - uses: actions/checkout@v4
       - name: Use Node.js
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@v6
         with:
           node-version: 'lts/*'
           check-latest: true

.github/workflows/steel.yml

@@ -157,7 +157,7 @@ jobs:
             workflow:
               - added|modified: '.github/workflows/solana-native.yml'
       - name: Use Node.js
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@v6
         with:
           node-version: 'lts/*'
           check-latest: true