[DOC] Tweaks for StringIO#fileno (#168) #562

Job	Run time
ruby-versions / Generate Ruby versions	5s
ubuntu-24.04 2.7	27s
ubuntu-24.04 3.3	22s
ubuntu-24.04 3.2	21s
ubuntu-22.04 2.7	33s
ubuntu-24.04 3.1	11s
ubuntu-24.04 3.4	22s
ubuntu-24.04 3.0	12s
ubuntu-24.04 truffleruby-head	27s
ubuntu-24.04 jruby-head	1m 11s
ubuntu-24.04 debug	23s
ubuntu-22.04 3.2	22s
ubuntu-22.04 3.0	15s
ubuntu-24.04 head	15s
ubuntu-22.04 3.3	14s
ubuntu-22.04 3.1	14s
ubuntu-22.04 debug	24s
ubuntu-22.04 jruby-head	1m 14s
ubuntu-22.04 head	20s
ubuntu-22.04 truffleruby-head	25s
ubuntu-22.04 3.4	18s
	8m 35s

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