chore: compress using zstd in docker test (#15430)

.github/workflows/docker-test-cont.yml

@@ -58,7 +58,7 @@ jobs:
         if: (env.TEST_CONTINUE)
         run: |
           set -ex
-          gzip -cvd docker-image/rsshub.tar.gz | docker load
+          zstd -d --stdout rssshub.tar.zst | docker load
           docker run -d \
             --name rsshub \
             -e NODE_ENV=dev \

.github/workflows/docker-test.yml

@@ -66,11 +66,11 @@ jobs:
         run: bash scripts/docker/test-docker.sh
 
       - name: Export Docker image
-        run: docker save rsshub:latest | gzip -1cf > rsshub.tar.gz
+        run: docker save rsshub:latest | zstdmt -o rsshub.tar.zst
 
       - name: Upload Docker image
         uses: actions/upload-artifact@v4
         with:
           name: docker-image
-          path: rsshub.tar.gz
+          path: rsshub.tar.zst
           retention-days: 1