chore: update workflows

Author: acgnhiki

.github/workflows/docker-hub.yml

@@ -18,7 +18,7 @@ jobs:
         uses: docker/setup-buildx-action@v1
 
       - name: Cache Docker layers
-        uses: actions/cache@v2
+        uses: actions/cache@v4
         with:
           path: /tmp/.buildx-cache
           key: ${{ runner.os }}-buildx-${{ github.sha }}

.github/workflows/ghcr.yml

@@ -17,7 +17,7 @@ jobs:
         uses: docker/setup-buildx-action@v1
 
       - name: Cache Docker layers
-        uses: actions/cache@v2
+        uses: actions/cache@v4
         with:
           path: /tmp/.buildx-cache
           key: ${{ runner.os }}-buildx-${{ github.sha }}