Update actions/cache to v4

Author: FestiveAkp

.github/workflows/cd.yml

@@ -16,10 +16,15 @@ jobs:
         uses: actions/checkout@master
 
       - name: Cache
-        uses: actions/cache@v2
+        uses: actions/cache@v4
         with:
-          path: ${{ github.workspace }}/.next/cache
-          key: ${{ runner.os }}-nextjs-${{ hashFiles('**/package-lock.json') }}
+          path: |
+            .next/cache
+          # Generate a new cache whenever packages or source files change.
+          key: ${{ runner.os }}-nextjs-${{ hashFiles('**/package-lock.json') }}-${{ hashFiles('**.[jt]s', '**.[jt]sx') }}
+          # If source files changed but packages didn't, rebuild from a prior cache.
+          restore-keys: |
+            ${{ runner.os }}-nextjs-${{ hashFiles('**/package-lock.json') }}-
 
       - name: Setup node env
         uses: actions/setup-node@v2.1.2