Update ci configuration: remove submodule test

.gitlab-ci.yml

 image: ubuntu:16.04
 
-variables:
-    GIT_SUBMODULE_STRATEGY: recursive
-
 before_script:
   - apt-get update && apt-get install -y g++ cmake libfftw3-dev liblapacke-dev
 
@@ -15,28 +12,3 @@ idg:
     - make install
     - source init-environment.sh
     - ctest --verbose
-
-idg2:
-  script:
-    - mkdir -p build/lib
-    - mkdir -p build/util
-    - mkdir -p build/bin
-    - mkdir install
-    - cd build/lib
-    - cmake ../../idg-lib -DCMAKE_INSTALL_PREFIX=../../install/lib
-    - make
-    - make install
-    - cd ../..
-    - source install/lib/init-environment.sh
-    - cd build/util
-    - cmake ../../idg-util -DCMAKE_INSTALL_PREFIX=../../install/util -DIDG_DIR=`realpath ../../install/lib`
-    - make
-    - make install
-    - cd ../..
-    - source install/util/init-environment.sh
-    - cd build/bin
-    - cmake ../../idg-bin -DCMAKE_INSTALL_PREFIX=../../install/bin -DIDG_DIR=`realpath ../../install/lib` -DIDG_UTIL_DIR=`realpath ../../install/util` -DBUILD_WITH_TESTS=On
-    - make
-    - make install
-    - source init-environment.sh
-    - ctest --verbose