test

Fix a warning for frozen string literal #163

Job	Run time
ruby-versions / Generate Ruby versions	3s
test (2.5, ubuntu-latest)	30s
test (2.5, windows-latest)	1m 50s
test (2.6, ubuntu-latest)	28s
test (2.6, macos-latest)	39s
test (2.6, windows-latest)	3m 25s
test (2.7, ubuntu-latest)	36s
test (2.7, macos-latest)	32s
test (2.7, windows-latest)	4m 44s
test (3.0, ubuntu-latest)	19s
test (3.0, macos-latest)	20s
test (3.0, windows-latest)	2m 47s
test (3.1, ubuntu-latest)	16s
test (3.1, macos-latest)	15s
test (3.1, windows-latest)	1m 48s
test (3.2, ubuntu-latest)	29s
test (3.2, macos-latest)	16s
test (3.2, windows-latest)	1m 46s
test (3.3, ubuntu-latest)	16s
test (3.3, macos-latest)	15s
test (3.3, windows-latest)	2m 34s
test (3.4, ubuntu-latest)	17s
test (3.4, macos-latest)	18s
test (3.4, windows-latest)	1m 35s
test (head, ubuntu-latest)	15s
test (head, macos-latest)	20s
test (head, windows-latest)	2m 0s
test (jruby, ubuntu-latest)	4m 34s
test (jruby-head, ubuntu-latest)	4m 48s
test (truffleruby, ubuntu-latest)	1m 36s
test (truffleruby-head, ubuntu-latest)	2m 4s
	41m 55s

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