Add merge request environment

.gitlab-ci.yml

 variables:
   DOCKER_DRIVER: overlay2
-  SITE_NAME: $CI_MERGE_REQUEST_PROJECT_PATH
 
 stages:
   - build
 
-.retry_twice:
+.general:
+  only: [merge_requests]
   retry:
     max: 2
     when:
@@ -13,19 +13,15 @@ stages:
       - stuck_or_timeout_failure
 
 natif-build:
-  variables:
-    CI_DEBUG_TRACE: "true"
-  extends: .retry_twice
+  extends: .general
   stage: build
   image: registry.orfeo-toolbox.org/sdinot/otb:ubuntu-18.04-gccV0.2
   script:
-    - echo $SITE_NAME
-#    - ctest -VV -S CI/main_ci.cmake \
-#      "-DCTEST_SITE:string=${CI_MERGE_REQUEST_PROJECT_PATH}_ubuntu-18.04"
+    - ctest -VV -S CI/main_ci.cmake -DIMAGE_NAME:string=ubuntu-18.04-gccV0.2
 
 shark-build:
-  extends: .retry_twice
+  extends: .general
   stage: build
   image: registry.orfeo-toolbox.org/sdinot/otb:ubuntu18.04-shark3.1.4
   script:
-    - ctest -VV -S CI/main_ci.cmake
\ No newline at end of file
+    - ctest -VV -S CI/main_ci.cmake -DIMAGE_NAME:string=ubuntu18.04-shark3.1.4
\ No newline at end of file

CI/main_ci.cmake

@@ -27,7 +27,7 @@ set (CTEST_BUILD_CONFIGURATION "Release")
 set (CTEST_CMAKE_GENERATOR "Unix Makefiles")
 
 set (CTEST_BUILD_NAME "$ENV{CI_MERGE_REQUEST_PROJECT_PATH}")
-set (CTEST_SITE "$ENV{CI_REGISTRY_IMAGE}")
+set (CTEST_SITE "${IMAGE_NAME}")
 
 # Directory variable
 set (CTEST_SOURCE_DIRECTORY "${OTB_SOURCE_DIR}")