[clangd][vscode] Turn on the semantic highlighting by default.

Summary:
We have turned on the flag manually and used it for a while, and don't see any
major issues, let's enable it by default.

Reviewers: ilya-biryukov

Subscribers: MaskRay, jkorous, arphaman, kadircet, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D68077

git-svn-id: https://llvm.org/svn/llvm-project/clang-tools-extra/trunk@372969 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/clangd/clients/clangd-vscode/package.json b/clangd/clients/clangd-vscode/package.json
index 96ec4c7..fdb6227 100644
--- a/clangd/clients/clangd-vscode/package.json
+++ b/clangd/clients/clangd-vscode/package.json
@@ -92,7 +92,7 @@
                 },
                 "clangd.semanticHighlighting": {
                     "type": "boolean",
-                    "default": "false",
+                    "default": "true",
                     "description": "Enable semantic highlighting in clangd"
                 }
             }