fix(ci): use portable test glob (test/*.test.js)

node --test on the runner's non-globstar sh never expanded
test/**/*.test.js, so CI reported 'Could not find'. All test files are
flat in test/, so a single * is correct and portable. Pre-existing
fragility surfaced by adding CI.

Co-Authored-By: jjohare <github@thedreamlab.uk>

Author: jjohare

package.json

@@ -8,7 +8,7 @@
     "dev": "echo 'Load extension from chrome://extensions in developer mode'",
     "build": "npm run bundle",
     "bundle": "node scripts/bundle.js",
-    "test": "node --test test/**/*.test.js",
+    "test": "node --test test/*.test.js",
     "lint": "eslint src/"
   },
   "keywords": [