[test] refresh builder defs once more after xt-common fix

dune/gdt/test/CMakeLists.txt

@@ -16,7 +16,7 @@ END_TESTCASES()
 if(DEFINED ENV{TRAVIS})
     include("builder_definitions.cmake")
     # make sure there's the same amount of builders in travis as bins from distribution
-    add_custom_target(regenerate_travis_yml ${CMAKE_BINARY_DIR}/dune-env-3
+    add_custom_target(regenerate_travis_yml ${CMAKE_BINARY_DIR}/dune-env
                         "${CMAKE_SOURCE_DIR}/.travis.yml.py" "${DXT_BIN_COUNT}" )
     add_dependencies(refresh_test_timings regenerate_travis_yml)
 endif(DEFINED ENV{TRAVIS})