bump minimum vscode version

1.52.0 is required for the language client/server

Author: bradlc

package.json

@@ -25,7 +25,7 @@
     "vscode"
   ],
   "engines": {
-    "vscode": "^1.33.0"
+    "vscode": "^1.52.0"
   },
   "categories": [
     "Linters",