chore(deps): batch-bump GitHub Actions to latest majors

Consolidates dependabot PRs #1-#5 into one atomic change to avoid sequential rebase churn (all 5 dependabot PRs touched the same 2 workflow files).

- actions/checkout: v4 → v6
- actions/configure-pages: v5 → v6
- actions/upload-artifact: v4 → v7
- actions/upload-pages-artifact: v3 → v5
- actions/deploy-pages: v4 → v5

Each individual bump's CI was green on dependabot's PR. Dependabot will auto-close PRs #1-#5 when this lands on main.

.github/workflows/build.yml

@@ -17,7 +17,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           submodules: recursive
           fetch-depth: 0
@@ -33,7 +33,7 @@ jobs:
         run: hugo --gc --minify --themesDir ../.. --printPathWarnings
 
       - name: Upload built site
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v7
         with:
           name: exampleSite-public
           path: exampleSite/public

.github/workflows/deploy.yml

@@ -18,13 +18,13 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           submodules: recursive
           fetch-depth: 0
 
       - id: pages
-        uses: actions/configure-pages@v5
+        uses: actions/configure-pages@v6
 
       - name: Setup Hugo Extended
         uses: peaceiris/actions-hugo@v3
@@ -42,7 +42,7 @@ jobs:
             --baseURL "${{ steps.pages.outputs.base_url }}/"
 
       - name: Upload Pages artifact
-        uses: actions/upload-pages-artifact@v3
+        uses: actions/upload-pages-artifact@v5
         with:
           path: exampleSite/public
 
@@ -54,4 +54,4 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - id: deployment
-        uses: actions/deploy-pages@v4
+        uses: actions/deploy-pages@v5