Tests

Update API from slack-api-ref@c408935 #1719

Job	Run time
test (ruby=2.7)	34s
test (ruby=2.7, concurrency=async-websocket)	39s
test (ruby=3.0)	26s
test (ruby=3.4)	21s
test (ruby=3.1)	27s
test (ruby=3.3)	29s
test (ruby=jruby-head)	2m 48s
test (ruby=3.2)	25s
test (ruby=ruby-head)	13s
coveralls	5s
	6m 27s

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