[DOC] Link `IO` to the official document #525

Job	Run time
ruby-versions / Generate Ruby versions	6s
ubuntu-24.04 3.0	15s
ubuntu-24.04 3.2	21s
ubuntu-24.04 2.7	51s
ubuntu-24.04 debug	25s
ubuntu-24.04 3.4	18s
ubuntu-24.04 3.3	18s
ubuntu-22.04 3.0	18s
ubuntu-24.04 head	19s
ubuntu-24.04 truffleruby-head	24s
ubuntu-22.04 3.1	22s
ubuntu-22.04 3.2	23s
ubuntu-22.04 debug	28s
ubuntu-22.04 3.3	14s
ubuntu-22.04 2.7	47s
ubuntu-24.04 jruby-head	1m 8s
ubuntu-22.04 3.4	19s
ubuntu-24.04 3.1	15s
ubuntu-22.04 head	15s
ubuntu-22.04 jruby-head	1m 7s
ubuntu-22.04 truffleruby-head	28s
	9m 21s

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