PUPPETEER_EXECUTABLE_PATH ignored on arm64 machines

Steps to reproduce

Tell us about your environment:

• Puppeteer version: 8.0.0
• Platform / OS version: MacOS Big Sur (Macbook Air M1)
• URLs (if applicable): -
• Node.js version: 15.11.0

What steps will reproduce the problem?

Please include code that reproduces the issue.

const puppeteer = require('puppeteer');

(async () => {
  const browser = await puppeteer.launch();
  const page = await browser.newPage();
  await page.goto('https://example.com');
  await page.screenshot({ path: 'example.png' });

  await browser.close();
})();

1. brew install chromium
2. npm install puppeteer
3. Save the above script as index.js
4. PUPPETEER_EXECUTABLE_PATH="/opt/homebrew/bin/chromium" node index.js

What is the expected result?

It should try to use /opt/homebrew/bin/chromium as the path to the browser executable.

What happens instead?

Puppeteer always overwrites the executable path specified via the environment variable internally and falls back to /usr/bin/chromium-browser. Setting executablePath explicitly in launch options works though:

// works, only setting via env var doesn't work
await puppeteer.launch({ executablePath: "/opt/homebrew/bin/chromium" });

[marvinhagemeister]

ping (to avoid stale bot)

[Saibamen]

This same on PuppeteerSharp 8.0.0 and Google Chrome 100.0.4896.127-1