Bump GitHub Actions to latest versions

- actions/checkout v4 -> v6
- actions/stale v9 -> v10

Author: bbatsov

.github/workflows/stale.yml

@@ -10,7 +10,7 @@ jobs:
       issues: write
       pull-requests: write
     steps:
-      - uses: actions/stale@v9
+      - uses: actions/stale@v10
         with:
           days-before-issue-stale: 90
           days-before-issue-close: 90

.github/workflows/test.yml

@@ -26,7 +26,7 @@ jobs:
       run: curl -fsSL https://raw.github.com/doublep/eldev/master/webinstall/github-eldev | sh
 
     - name: Check out the source code
-      uses: actions/checkout@v4
+      uses: actions/checkout@v6
 
     - name: Test the project
       run: |