Darwin uses DYLD_LIBRARY_PATH, not LD_LIBRARY_PATH

--- meson.build
+++ meson.build	2022-03-02 07:44:52.000000000 -0500
@@ -574,7 +574,7 @@
 tests_environment.set('GJS_PATH', '')
 tests_environment.prepend('GI_TYPELIB_PATH', meson.current_build_dir(),
     js_tests_builddir)
-tests_environment.prepend('LD_LIBRARY_PATH', meson.current_build_dir(),
+tests_environment.prepend('DYLD_LIBRARY_PATH', meson.current_build_dir(),
     js_tests_builddir)
 tests_environment.set('G_FILENAME_ENCODING', 'latin1')
 tests_environment.set('LSAN_OPTIONS', 'exitcode=23,suppressions=@0@'.format(