tentative fix for test failing when in submodule

gcontini

2020-05-16 e16a991667d8e5c49cafb869d4844b80fc323ed8

 test/library/CMakeLists.txt

@@ -14,7 +14,7 @@
ELSE(WIN32)
    add_executable(
       test_os_linux
       Os_Linux_test.cpp
       os_linux_test.cpp
   )

   target_link_libraries(