[clangd] Use WorkScheduler.run() in ClangdServer::resolveTypeHierarchy()

[nridge]

As discussed in https://reviews.llvm.org/D91123#inline-856770

[kadircet]

thanks!

clang-tools-extra/clangd/ClangdServer.cpp

void ClangdServer::typeHierarchy(PathRef File, Position Pos, int Resolve,
   };
 
   WorkScheduler.runWithAST("Type Hierarchy", File, std::move(Action));
 }
 
 void ClangdServer::resolveTypeHierarchy(
     TypeHierarchyItem Item, int Resolve, TypeHierarchyDirection Direction,
     Callback<llvm::Optional<TypeHierarchyItem>> CB) {
+  WorkScheduler.run(
+      "Resolve Type Hierarchy", "", [=, CB = std::move(CB)]() mutable {
         clangd::resolveTypeHierarchy(Item, Resolve, Direction, Index);
         CB(Item);
+      });
 }
 
 void ClangdServer::prepareCallHierarchy(
     PathRef File, Position Pos, Callback<std::vector<CallHierarchyItem>> CB) {
   auto Action = [File = File.str(), Pos,
                  CB = std::move(CB)](Expected<InputsAndAST> InpAST) mutable {
     if (!InpAST)
       return CB(InpAST.takeError());