Remove unit tests with Node 16 #446

Job	Run time
test-unit-parallel (18, ubuntu)	1m 31s
lint	1m 35s
test-unit-parallel (18, macos)	2m 2s
build	1m 1s
test-unit-parallel (18, windows)	8m 39s
test-api-parallel (18, ubuntu, chromium)	2m 25s
test-playwright-parallel (18, ubuntu, chromium)	2m 23s
test-api-parallel (18, ubuntu, firefox)	3m 6s
test-playwright-parallel (18, ubuntu, firefox)	1m 55s
test-playwright-parallel (18, ubuntu, webkit)	2m 59s
test-api (18, windows, chromium)	10m 27s
release-dry-run (18)	2m 42s
test-api (18, windows, firefox)	9m 14s
test-unit-coverage	1m 28s
	51m 27s

Provide feedback