Export of internal Abseil changes

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32b444c0540e8255cc216171aba57639903edc22 by CJ Johnson <[email protected]>:

Add missing `final` to `absl::Cleanup` since it is not an interface type and should never be used as a base class.

PiperOrigin-RevId: 359045692
GitOrigin-RevId: 32b444c0540e8255cc216171aba57639903edc22
Change-Id: I4f72714cd6f2e101709f31958af28b358f15646b

Author: Abseil Team

absl/cleanup/cleanup.h

@@ -78,7 +78,7 @@ namespace absl {
 ABSL_NAMESPACE_BEGIN
 
 template <typename Arg, typename Callback = void()>
-class ABSL_MUST_USE_RESULT Cleanup {
+class ABSL_MUST_USE_RESULT Cleanup final {
   static_assert(cleanup_internal::WasDeduced<Arg>(),
                 "Explicit template parameters are not supported.");