[DOC] Doc for StringIO#each_byte #530

Job	Run time
ruby-versions / Generate Ruby versions	5s
ubuntu-24.04 3.0	14s
ubuntu-24.04 3.3	14s
ubuntu-24.04 2.7	47s
ubuntu-24.04 3.2	18s
ubuntu-24.04 3.4	18s
ubuntu-24.04 3.1	14s
ubuntu-24.04 debug	23s
ubuntu-22.04 2.7	49s
ubuntu-24.04 truffleruby-head	28s
ubuntu-24.04 head	16s
ubuntu-22.04 3.3	18s
ubuntu-22.04 3.2	22s
ubuntu-22.04 3.4	22s
ubuntu-22.04 head	14s
ubuntu-22.04 debug	24s
ubuntu-22.04 3.0	21s
ubuntu-22.04 3.1	23s
ubuntu-22.04 truffleruby-head	26s
ubuntu-22.04 jruby-head	1m 7s
ubuntu-24.04 jruby-head	1m 9s
	9m 12s

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