fix(snippet): cmake path

Author: eseiler

test/snippet/CMakeLists.txt

@@ -36,7 +36,7 @@ macro (sharg_snippet test_name_prefix snippet snippet_base_path)
     add_test (NAME "${snippet_compare_test_target}"
               COMMAND ${CMAKE_COMMAND} -DTARGET_FILE=$<TARGET_FILE:${target}>
                       -DSOURCE_FILE=${snippet_base_path}/${snippet} -P
-                      "${CMAKE_SOURCE_DIR}/compare_snippet_output.cmake")
+                      "${CMAKE_CURRENT_SOURCE_DIR}/compare_snippet_output.cmake")
 
     # disable version checker, as it interferes with comparing the snippet output
     set_tests_properties ("${snippet_compare_test_target}" PROPERTIES ENVIRONMENT SHARG_NO_VERSION_CHECK=0)