chore: add explicit chai imports to test files

Import expect from chai in test files instead of relying on globals

Co-authored-by: nikku <[email protected]>

Author: Copilot

package-lock.json

@@ -1,3 +1,5 @@
+import { expect } from 'chai';
+
 describe('distro', function() {
 
   it('should expose CJS bundle', function() {

test/distro/distroSpec.js

@@ -1,3 +1,5 @@
+import { expect } from 'chai';
+
 import semver from 'semver';
 
 import {