Changed snapshot image tag format and releasing of `latest` workflow

.gitlab-ci.yml

@@ -2,7 +2,7 @@ services:
   - docker:dind
 
 variables:
-  IMAGE_SNAPSHOT: $CI_REGISTRY_IMAGE:$CI_COMMIT_REF_NAME-snapshot
+  IMAGE_SNAPSHOT: $CI_REGISTRY_IMAGE:$CI_COMMIT_SHA
   IMAGE: $CI_REGISTRY_IMAGE:$CI_COMMIT_REF_NAME
   IMAGE_LATEST: $CI_REGISTRY_IMAGE:latest
 
@@ -26,6 +26,8 @@ build:
 
 test:
   stage: test
+  variables:
+    GIT_STRATEGY: none
   script:
     - docker pull $IMAGE_SNAPSHOT
     - docker run $IMAGE_SNAPSHOT echo "Running tests..."
@@ -34,21 +36,24 @@ test:
 
 release:
   stage: release
+  variables:
+    GIT_STRATEGY: none
   script:
     - docker pull $IMAGE_SNAPSHOT
     - docker tag $IMAGE_SNAPSHOT $IMAGE
     - docker push $IMAGE
   tags:
     - dind
-  except:
-    - master
 
 release:latest:
   stage: release
+  variables:
+    GIT_STRATEGY: none
   script:
     - docker pull $IMAGE_SNAPSHOT
     - docker tag $IMAGE_SNAPSHOT $IMAGE_LATEST
     - docker push $IMAGE_LATEST
+  when: manual
   tags:
     - dind
   only: