Apply suggestions from code review

Co-authored-by: Graydon Hoare <[email protected]>

Author: bboston7

src/main/Application.h

@@ -171,7 +171,7 @@ class Application
         WORKER,
         EVICTION,
         OVERLAY,
-        LEDGER_CLOSE
+        APPLY
     };
 
     virtual ~Application(){};

src/main/ApplicationImpl.cpp

@@ -192,7 +192,7 @@ ApplicationImpl::ApplicationImpl(VirtualClock& clock, Config const& cfg)
     {
         mLedgerCloseThread =
             std::thread{[this]() { mLedgerCloseIOContext->run(); }};
-        mThreadTypes[mLedgerCloseThread->get_id()] = ThreadType::LEDGER_CLOSE;
+        mThreadTypes[mLedgerCloseThread->get_id()] = ThreadType::APPLY;
     }
 }