update workflows to v4 (#118)

Author: woodiertexas

.github/workflows/commit-preview.yaml

@@ -11,7 +11,7 @@ jobs:
     name: Generate commit preview
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Enable Corepack shims
         run: corepack enable

.github/workflows/pr-preview.yaml

@@ -10,7 +10,7 @@ jobs:
     name: Generate PR preview
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Enable Corepack shims
         run: corepack enable
@@ -22,7 +22,7 @@ jobs:
         run: pnpm build
 
       - name: Upload HTML artifact
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v4
         with:
           name: website-html
           path: build