cpp_test_suite/environment/CMakeLists.txt: Use correct folder for tango_host file

The PROJECT_BINARY_DIR points to CMAKE_BINARY_DIR/cpp_test_suite but we
want to have CMAKE_BINARY_DIR/ccp_test_suite/environment.

Let's use no path as configure_file defaults to CMAKE_CURRENT_BINARY_DIR
anyway and we use later calls in the same way.

This issue was found with CMAKE 3.13.4 from debian buster.

Author: t-b

cpp_test_suite/environment/CMakeLists.txt

@@ -1,5 +1,5 @@
 #TODO windows
-configure_file(tango_host.cmake ${PROJECT_BINARY_DIR}/tango_host @ONLY)
+configure_file(tango_host.cmake tango_host @ONLY)
 
 configure_file(pre_test.sh.cmake pre_test.sh @ONLY)
 execute_process(COMMAND chmod +x ${CMAKE_CURRENT_BINARY_DIR}/pre_test.sh)