Fix empty arg handling in extension (#5083)

Oops, broken in #5056

utils/vscode/package.json

@@ -1,7 +1,7 @@
 {
   "name": "carbon-vscode",
   "displayName": "Carbon Language",
-  "version": "0.0.6",
+  "version": "0.0.7",
   "publisher": "carbon-lang",
   "description": "Carbon language support for Visual Studio Code.",
   "repository": {

utils/vscode/src/extension.ts

@@ -30,7 +30,7 @@ function splitQuotedString(argsString: string): string[] {
   const args: string[] = [];
   let arg = '';
   // Track whether there's an arg to handle `""` and similar.
-  let hasArg = true;
+  let hasArg = false;
   // Whether this is in a quote-delimited section.
   let inSingleQuotes = false;
   let inDoubleQuotes = false;