macos

[DOC] Tweaks for StringIO#close #497

Job	Run time
ruby-versions / Generate Ruby versions	4s
macos-13 3.0	21s
macos-13 2.7	1m 23s
macos-13 3.1	26s
macos-13 3.2	34s
macos-13 head	32s
macos-13 3.3	20s
macos-13 3.4	21s
macos-14 2.7	41s
macos-14 jruby-head	49s
macos-14 head	18s
macos-14 debug	20s
macos-14 3.2	18s
macos-14 3.3	16s
macos-14 3.1	15s
macos-14 3.0	15s
macos-13 debug	31s
macos-14 3.4	13s
macos-13 jruby-head	1m 17s
	9m 14s

Provide feedback