pin puppeteer to avoid taking on libgbm1 dependency

jupyterlab/browser_check.py

@@ -144,7 +144,7 @@ async def run_browser(url):
     if not osp.exists(osp.join(target, 'node_modules')):
         os.makedirs(target)
         await run_async_process(["jlpm", "init", "-y"], cwd=target)
-        await run_async_process(["jlpm", "add", "puppeteer"], cwd=target)
+        await run_async_process(["jlpm", "add", "puppeteer@^2"], cwd=target)
     shutil.copy(osp.join(here, 'chrome-test.js'), osp.join(target, 'chrome-test.js'))
     await run_async_process(["node", "chrome-test.js", url], cwd=target)