Fix rule example to be correct #366

Job	Run time
ruby-versions / Generate Ruby versions	3s
test (ubuntu-latest, 2.3)	37s
test (ubuntu-latest, 2.4)	38s
test (ubuntu-latest, 2.5)	37s
test (ubuntu-latest, 2.6)	39s
test (ubuntu-latest, 2.7)	39s
test (ubuntu-latest, 3.0)	18s
test (ubuntu-latest, 3.1)	16s
test (ubuntu-latest, 3.2)	15s
test (ubuntu-latest, head)	16s
test (ubuntu-latest, jruby)	4m 5s
test (ubuntu-latest, jruby-head)	4m 19s
test (macos-latest, 2.3)	1m 33s
test (macos-latest, 2.4)	1m 50s
test (macos-latest, 2.5)	1m 31s
test (macos-latest, 2.6)	2m 0s
test (macos-latest, 2.7)	1m 24s
test (macos-latest, 3.0)	21s
test (macos-latest, 3.1)	31s
test (macos-latest, 3.2)	41s
test (macos-latest, head)	33s
test (macos-latest, jruby)	4m 57s
test (macos-latest, jruby-head)	3m 17s
test (windows-latest, 2.3)	1m 30s
test (windows-latest, 2.4)	1m 45s
test (windows-latest, 2.5)	2m 13s
test (windows-latest, 2.6)	2m 31s
test (windows-latest, 2.7)	2m 25s
test (windows-latest, 3.0)	1m 39s
test (windows-latest, 3.1)	1m 47s
test (windows-latest, 3.2)	2m 57s
test (windows-latest, head)	1m 16s
	49m 23s

Provide feedback