Fix CI. Add include shared script and remove dependency backend_cpu

.gitlab/ci/build.gitlab-ci.yml

+include:
+  - remote: 'https://gitlab.eclipse.org/eclipse/aidge/gitlab_shared_files/-/raw/main/.gitlab/ci/shared_script.gitlab-ci.yml'
+
 build:ubuntu_cpp:
   stage: build
   needs: []
@@ -8,10 +11,7 @@ build:ubuntu_cpp:
     - DEPENDENCY_JOB="build:ubuntu_cpp"
     # aidge_core
     - DEPENDENCY_NAME="aidge_core" 
-    - !reference [.download_dependency, script]   
-    # aidge_backend_cpu
-    - DEPENDENCY_NAME="aidge_backend_cpu"
-    - !reference [.download_dependency, script]    
+    - !reference [.download_dependency, script]       
   
     # Build current module
     - export CMAKE_PREFIX_PATH=../install_cpp
@@ -37,9 +37,6 @@ build:ubuntu_cpp_g++10:
     # aidge_core
     - DEPENDENCY_NAME="aidge_core" 
     - !reference [.download_dependency, script]   
-    # aidge_backend_cpu
-    - DEPENDENCY_NAME="aidge_backend_cpu"
-    - !reference [.download_dependency, script]    
 
     # Build current module
     - export CMAKE_PREFIX_PATH=../install_cpp
@@ -62,10 +59,7 @@ build:ubuntu_cpp_g++12:
     - DEPENDENCY_JOB="build:ubuntu_cpp"
     # aidge_core
     - DEPENDENCY_NAME="aidge_core" 
-    - !reference [.download_dependency, script]   
-    # aidge_backend_cpu
-    - DEPENDENCY_NAME="aidge_backend_cpu"
-    - !reference [.download_dependency, script]    
+    - !reference [.download_dependency, script]      
 
     # Build current module
     - export CMAKE_PREFIX_PATH=../install_cpp
@@ -88,9 +82,6 @@ build:ubuntu_cpp_clang12:
     - DEPENDENCY_JOB="build:ubuntu_cpp"
     # aidge_core
     - DEPENDENCY_NAME="aidge_core" 
-    - !reference [.download_dependency, script]   
-    # aidge_backend_cpu
-    - DEPENDENCY_NAME="aidge_backend_cpu"
     - !reference [.download_dependency, script]    
 
     # Build current module
@@ -114,10 +105,7 @@ build:ubuntu_cpp_clang15:
     - DEPENDENCY_JOB="build:ubuntu_cpp"
     # aidge_core
     - DEPENDENCY_NAME="aidge_core" 
-    - !reference [.download_dependency, script]   
-    # aidge_backend_cpu
-    - DEPENDENCY_NAME="aidge_backend_cpu"
-    - !reference [.download_dependency, script]    
+    - !reference [.download_dependency, script]     
 
     # Build current module
     - export CMAKE_PREFIX_PATH=../install_cpp
@@ -140,9 +128,6 @@ build:ubuntu_python:
     - DEPENDENCY_JOB="build:ubuntu_python"
     # aidge_core
     - DEPENDENCY_NAME="aidge_core" 
-    - !reference [.download_dependency, script]   
-    # aidge_backend_cpu
-    - DEPENDENCY_NAME="aidge_backend_cpu"
     - !reference [.download_dependency, script]    
 
     - python3 -m pip install virtualenv