Fix build-push-action version

Author: fwcd

.github/workflows/docker.yml

@@ -29,7 +29,7 @@ jobs:
         with:
           images: fwcd/kotlin-language-server
       - name: Build and push image
-        uses: docker/build-push-action@v1
+        uses: docker/build-push-action@v4
         with:
           context: .
           platforms: linux/amd64,linux/arm64/v8