[clangd] Bump vscode-clangd v0.0.18
[clangd] Bump vscode-clangd v0.0.18

CHANGELOG:
- enable semantic highlighting by default
- upgrade the LSP dependencies to pickup the incoming LSP v3.15.0

git-svn-id: a34e9779ed74578ad5922b3306b3d80a0c825546@372981 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/clang-tools-extra,llvm-mirror/clang-tools-extra,llvm-mirror/clang-tools-extra,llvm-mirror/clang-tools-extra