absl::debugging depends on leak_check, so isn't in devel/abseil-cpp

Index: cmake/abseil-cpp.cmake
--- cmake/abseil-cpp.cmake.orig
+++ cmake/abseil-cpp.cmake
@@ -64,7 +64,6 @@ else()
     absl::cleanup
     absl::cord
     absl::core_headers
-    absl::debugging
     absl::die_if_null
     absl::dynamic_annotations
     absl::flags