chore: remove node<14 tests

[dummdidumm]

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[benmccann]

I was going to ask if we should keep 12 for awhile longer, but 20 comes out next week and 14 is EOL at the end of the month, so I think supporting 14 still is generous enough

[benmccann]

lgtm, but will need to fix the test failures before merging

[benmccann]

I think we would still need this, but I upgraded puppeteer so that it's no longer necessary and we can run the tests locally. I can reproduce the test failures locally, but have no clue why they're happening

[benmccann]

Hmm. Maybe the test failures are related to some of the recently merged PRs. I see it expecting add_resize_listener, which was removed in #8022 and I see the tests also failing in master since that PR.