Updated gitlab ci file

.gitlab-ci.yml

@@ -3,10 +3,8 @@ merge:
   stage: test
   services:
     - docker:dind
-  variables:
-    DOCKER_IMAGE_NAME: $CI_REGISTRY_IMAGE:$CI_COMMIT_REF_SLUG
   script:
-    - docker build -t "$DOCKER_IMAGE_NAME" .
+    - docker build -t "$CI_REGISTRY_IMAGE:merge-request" .
   rules:
     - if: '$CI_PIPELINE_SOURCE == "merge_request_event"'
 
@@ -15,14 +13,16 @@ build:
   stage: build
   services:
     - docker:dind
-  variables:
-    DOCKER_IMAGE_NAME: $CI_REGISTRY_IMAGE:$CI_COMMIT_REF_SLUG
   before_script:
     - docker login -u "$CI_REGISTRY_USER" -p "$CI_REGISTRY_PASSWORD" $CI_REGISTRY
   script:
     - |
-        docker build -t "$DOCKER_IMAGE_NAME" .
-        docker tag "$DOCKER_IMAGE_NAME" "$CI_REGISTRY_IMAGE:main"
+        docker build -t "illegitimate" .
+
+        docker tag "illegitimate" "$CI_REGISTRY_IMAGE:$CI_COMMIT_SHORT_SHA"
+        docker push "$CI_REGISTRY_IMAGE:$CI_COMMIT_SHORT_SHA"
+
+        docker tag "illegitimate" "$CI_REGISTRY_IMAGE:main"
         docker push "$CI_REGISTRY_IMAGE:main"
   rules:
     - if: '$CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH'