[CMake] example-robot-data is required only for tests

CMakeLists.txt

@@ -37,9 +37,9 @@ CHECK_MINIMAL_CXX_STANDARD(11 ENFORCE)
 # Project dependencies
 ADD_PROJECT_DEPENDENCY(dynamic-graph REQUIRED PKG_CONFIG_REQUIRES dynamic-graph)
 ADD_PROJECT_DEPENDENCY(pinocchio REQUIRED PKG_CONFIG_REQUIRES pinocchio)
-ADD_PROJECT_DEPENDENCY(example-robot-data)
 ADD_PROJECT_DEPENDENCY(Boost REQUIRED COMPONENTS regex)
 IF(BUILD_TESTING)
+  ADD_PROJECT_DEPENDENCY(example-robot-data)
   FIND_PACKAGE(Boost REQUIRED COMPONENTS unit_test_framework program_options)
 ENDIF()