add missing dep

Author: Brad Cornes

packages/tailwindcss-vscode/package.json

@@ -65,6 +65,7 @@
     "dlv": "^1.1.3",
     "glob-exec": "^0.1.1",
     "mkdirp": "^1.0.3",
+    "tailwindcss-language-server": "0.0.1",
     "tslint": "^5.16.0",
     "typescript": "^3.8.3",
     "vscode-languageclient": "^5.2.1"