ClangdServer.cpp: Suppress a warning. [-Wunused-lambda-capture]

llvm-svn: 307068
diff --git a/clang-tools-extra/clangd/ClangdServer.cpp b/clang-tools-extra/clangd/ClangdServer.cpp
index 5e66884..0a1f927 100644
--- a/clang-tools-extra/clangd/ClangdServer.cpp
+++ b/clang-tools-extra/clangd/ClangdServer.cpp
@@ -258,6 +258,7 @@
 
   WorkScheduler.addToEnd([this, &DumpPromise, File, Version]() {
     assert(DraftMgr.getVersion(File) == Version && "Version has changed");
+    (void)Version;
 
     Units.runOnExistingUnit(File, [&DumpPromise](ClangdUnit &Unit) {
       std::string Result;