update puppeteer and add logs

[tanhauhau]

trying to learn why

  1) custom-elements
       "before all" hook for "custom-method":
     Error: Timeout of 10000ms exceeded. For async tests and hooks, ensure "done()" is called; if returning a Promise, ensure it resolves. (/home/runner/work/svelte/svelte/test/test.js)
  

  2) custom-elements
       "after all" hook for "props":
     TypeError: Cannot read property 'close' of undefined
      at Context.after (test/custom-elements/index.js:53:17)

Example

the logs itself didn't explain much. and the error usually gone after a retry on CI.

this PR is a "throw at the wall and see what sticks" attempt on investigating what's wrong.

• Added a log right after every statement for before in custom-elements test suite
• Upgraded puppeteer, and hopefully it's better. 🙈

[benmccann]

could also consider console.info or console.debug