Image build is optimized.

.gitlab-ci.yml

@@ -22,7 +22,7 @@ variables:
 
 build:
   stage: build
-  image: docker:latest
+  image: docker:dind:20.10.21
   services:
     - name: docker:dind:20.10.21
       command: ["--tls=false", "--storage-driver=overlay2", "--mtu=1500", "--data-root=/mnt/volume"]
@@ -36,7 +36,7 @@ build:
     - docker system prune -a -f
     - docker volume prune -f
   script:
-    - docker build --no-cache --progress=plain -t flask-backend-full -f flask_ml_api/Dockerfile .
+    - docker build --cache-from=flask-backend-full --no-cache --progress=plain -t flask-backend-full -f flask_ml_api/Dockerfile .
   cache:
     key: build-cache
     paths: