Attempt to fix Mac CI (#2120)

This has worked in the past. Not promising that it's only a patch bump,
but worth a shot

## Checklist

- [ ] I have added
[tests](https://www.cursorless.org/docs/contributing/test-case-recorder/)
- [ ] I have updated the
[docs](https://github.com/cursorless-dev/cursorless/tree/main/docs) and
[cheatsheet](https://github.com/cursorless-dev/cursorless/tree/main/cursorless-talon/src/cheatsheet)
- [ ] I have not broken the cheatsheet

Author: pokey

packages/test-harness/package.json

@@ -28,7 +28,7 @@
   "devDependencies": {
     "@types/glob": "^7.1.3",
     "@types/mocha": "^10.0.3",
-    "@vscode/test-electron": "^2.3.6",
+    "@vscode/test-electron": "^2.3.8",
     "mocha": "^10.2.0"
   },
   "types": "./out/index.d.ts",