Don't directly invoke handle destructors in RAMCacheComponent

Summary: It's undefined behavior to call an item's destructor twice (see [this comment](https://www.internalfb.com/diff/D88516565?dst_version_fbid=1376806097214701&transaction_fbid=1562143038240295)), moving the handle out into a temporary is the more idiomatic way to destroy the rvalue ref argument.

Reviewed By: AlnisM

Differential Revision: D90253324

fbshipit-source-id: 6e1d9797ef9532746c35e3c9bdc7feb1cea1c36a

Author: Rob Lyerly

cachelib/interface/components/RAMCacheComponent.cpp

@@ -186,7 +186,7 @@ folly::coro::Task<UnitResult> RAMCacheComponent::insert(
     co_return makeError(Error::Code::INSERT_FAILED, e.what());
   }
 
-  handle.~AllocatedHandle();
+  auto _ = std::move(handle);
   co_return folly::unit;
 }
 
@@ -215,7 +215,7 @@ RAMCacheComponent::insertOrReplace(AllocatedHandle&& handle) {
     co_return makeError(Error::Code::INSERT_FAILED, e.what());
   }
 
-  handle.~AllocatedHandle();
+  auto _ = std::move(handle);
   if (replacedHandle) {
     co_return toGenericHandle<AllocatedHandle>(*this, replacedHandle);
   } else {
@@ -261,7 +261,7 @@ folly::coro::Task<UnitResult> RAMCacheComponent::remove(ReadHandle&& handle) {
     co_return makeError(Error::Code::REMOVE_FAILED, e.what());
   }
 
-  handle.~ReadHandle();
+  auto _ = std::move(handle);
   co_return folly::unit;
 }