Remove --test argument

harness/test/index.js

+import './cli-test.js'
+import './runner-test.js'

package.json

@@ -23,8 +23,8 @@
     "coverage": "CODE_COVERAGE=1 c8 npm run test:ci",
     "format": "node npm/format.js harness,npm",
     "lint": "eslint \"{harness,npm}/**/*.js\" \"harness/test/**/*.js\"",
-    "test": "node --test harness/test/**.js",
-    "test:ci": "node --test-reporter=dot --test-reporter=junit --test-reporter-destination=stdout --test-reporter-destination=reports/tests-xunit.xml --test harness/test/**.js",
+    "test": "node harness/test/index.js",
+    "test:ci": "node --test-reporter=dot --test-reporter=junit --test-reporter-destination=stdout --test-reporter-destination=reports/tests-xunit.xml harness/test/index.js",
     "prepublishOnly": "npx -y downdoc --prepublish",
     "postpublish": "npx -y downdoc --postpublish"
   },
@@ -63,6 +63,6 @@
     "."
   ],
   "volta": {
-    "node": "20.8.0"
+    "node": "20.12.0"
   }
 }