test: add debug logging to diagnose CI issue

tests/src/rules/no-unused-modules.js

@@ -4,7 +4,7 @@ import typescriptConfig from '../../../config/typescript';
 
 import { RuleTester } from '../rule-tester';
 import { expect } from 'chai';
-import { execSync } from 'child_process';
+import { exec, execSync } from 'child_process';
 import fs from 'fs';
 import eslintPkg from 'eslint/package.json';
 import path from 'path';
@@ -1501,6 +1501,13 @@ describe('parser ignores prefixes like BOM and hashbang', () => {
 
     let errorMessage = '';
 
+    // Build the plugin
+    try {
+      execSync('npm run build');
+    } catch (_) {
+      /* ignore */
+    }
+
     // Install the plugin and run the lint command in the temp directory
     try {
       execSync(`npm install -D ${process.cwd()} && npm run lint`, { cwd: tempDir.name });