Remove unused includes from AsyncFileWriterTest.cpp

Summary:
Remove three unused `#include` directives from `fbcode/folly/logging/test/AsyncFileWriterTest.cpp`:

- `folly/init/Init.h` — no symbols (`folly::Init`, `InitOptions`) are referenced
- `folly/logging/Init.h` — no symbols (`initLogging`, `FOLLY_INIT_LOGGING_CONFIG`) are referenced
- `folly/test/TestUtils.h` — no symbols (`EXPECT_THROW_RE`, `EXPECT_THROW_ERRNO`) are referenced

Reviewed By: lexprfuncall

Differential Revision: D95404348

fbshipit-source-id: 8d0ab6f31c573c03937b34e4522d84aab23d1c51

Author: yfeldblum

third-party/folly/src/folly/logging/test/AsyncFileWriterTest.cpp

@@ -30,9 +30,7 @@
 #include <folly/Synchronized.h>
 #include <folly/futures/Future.h>
 #include <folly/futures/Promise.h>
-#include <folly/init/Init.h>
 #include <folly/lang/SafeAssert.h>
-#include <folly/logging/Init.h>
 #include <folly/logging/LoggerDB.h>
 #include <folly/logging/xlog.h>
 #include <folly/portability/Config.h>
@@ -42,7 +40,6 @@
 #include <folly/portability/Unistd.h>
 #include <folly/system/ThreadId.h>
 #include <folly/system/ThreadName.h>
-#include <folly/test/TestUtils.h>
 #include <folly/testing/TestUtil.h>
 
 DEFINE_int64(