add cleanup job to clear build directory

.gitlab-ci.yml

@@ -1,5 +1,6 @@
 stages:
 - build
+- cleanup-build
 - deploy
 
 variables:
@@ -15,18 +16,29 @@ variables:
 build:
   stage: build
   variables:
-    # instance 
-    GIT_CLONE_PATH: $CI_BUILDS_DIR/$CI_RUNNER_SHORT_TOKEN/$CI_PROJECT_NAME-$CI_JOB_ID
+    # instance the build job to avoid multiple jobs running in the same project folder
+    GIT_CLONE_PATH: $CI_BUILDS_DIR/$CI_RUNNER_SHORT_TOKEN/$CI_PROJECT_NAME-build-$CI_PIPELINE_ID
   script:
   - echo "cloned to $GIT_CLONE_PATH"
   - chmod +x ./ci/build.sh
   - ./ci/build.sh $UNITY_VERSION
-  after_script:
-  - rm -r $GIT_CLONE_PATH
+  
   artifacts:
     name: $CI_PROJECT_NAME-$CI_PIPELINE_ID
     paths:
     - $BUILD_DIR
+    
+# remove the directory created by the build job. in a separate job 
+cleanup-build:
+  stage: cleanup-build
+  variables:
+    CLEANUP_PATH: $CI_BUILDS_DIR/$CI_RUNNER_SHORT_TOKEN/$CI_PROJECT_NAME-build-$CI_PIPELINE_ID
+  script:
+  - echo "cleaning up build directory"
+  - rm -r $CLEANUP_PATH
+  dependencies:
+  - build
+
 
 # deploy to internal testing track
 deploy-dev: