Adding the rest back in.

node_modules/undici/lib/mock/mock-errors.js

@@ -0,0 +1,17 @@
+'use strict'
+
+const { UndiciError } = require('../core/errors')
+
+class MockNotMatchedError extends UndiciError {
+  constructor (message) {
+    super(message)
+    Error.captureStackTrace(this, MockNotMatchedError)
+    this.name = 'MockNotMatchedError'
+    this.message = message || 'The request does not match any registered mock dispatches'
+    this.code = 'UND_MOCK_ERR_MOCK_NOT_MATCHED'
+  }
+}
+
+module.exports = {
+  MockNotMatchedError
+}