[gn build] Port 30ba8be

Author: llvmgnsyncbot

llvm/utils/gn/secondary/clang-tools-extra/clangd/unittests/BUILD.gn

@@ -80,6 +80,7 @@ unittest("ClangdTests") {
     "GlobalCompilationDatabaseTests.cpp",
     "HeaderSourceSwitchTests.cpp",
     "HeadersTests.cpp",
+    "HeuristicResolverTests.cpp",
     "HoverTests.cpp",
     "IncludeCleanerTests.cpp",
     "IndexActionTests.cpp",