[DOC] Tweaks for StringIO#eof? #541

Job	Run time
ruby-versions / Generate Ruby versions	4s
ubuntu-24.04 2.7	34s
ubuntu-24.04 3.0	21s
ubuntu-24.04 3.2	30s
ubuntu-24.04 truffleruby-head	40s
ubuntu-24.04 3.4	24s
ubuntu-22.04 2.7	35s
ubuntu-24.04 3.1	26s
ubuntu-24.04 head	23s
ubuntu-24.04 jruby-head	1m 16s
ubuntu-22.04 3.2	28s
ubuntu-24.04 3.3	27s
ubuntu-24.04 debug	30s
ubuntu-22.04 3.4	32s
ubuntu-22.04 3.0	21s
ubuntu-22.04 truffleruby-head	49s
ubuntu-22.04 debug	30s
ubuntu-22.04 3.3	26s
ubuntu-22.04 3.1	28s
ubuntu-22.04 head	23s
ubuntu-22.04 jruby-head	1m 20s
	11m 27s

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