[DOC] Tweaks for StringIO#lineno (#191) #614

Job	Run time
ruby-versions / Generate Ruby versions	3s
ubuntu-24.04 3.2	18s
ubuntu-24.04 3.3	21s
ubuntu-24.04 2.7	48s
ubuntu-24.04 3.1	14s
ubuntu-24.04 3.4	16s
ubuntu-24.04 3.0	16s
ubuntu-24.04 jruby-head	1m 1s
ubuntu-24.04 truffleruby-head	26s
ubuntu-24.04 debug	21s
ubuntu-22.04 3.1	13s
ubuntu-22.04 3.2	17s
ubuntu-22.04 head	14s
ubuntu-22.04 3.3	16s
ubuntu-24.04 head	18s
ubuntu-22.04 3.0	17s
ubuntu-22.04 2.7	46s
ubuntu-22.04 jruby-head	1m 17s
ubuntu-22.04 3.4	19s
ubuntu-22.04 debug	25s
ubuntu-22.04 truffleruby-head	27s
	8m 53s

Provide feedback