Change version guard in language/for_spec to ruby_bug #1654

Job	Run time
RuboCop	28s
specs (ubuntu, 3.0.6)	1m 27s
specs (ubuntu, 3.1.4)	1m 32s
specs (ubuntu, 3.2.2)	1m 27s
specs (ubuntu, 3.3.0)	1m 22s
specs (macos, 3.0.6)	1m 24s
specs (macos, 3.1.4)	1m 24s
specs (macos, 3.2.2)	1m 15s
specs (macos, 3.3.0)	1m 13s
specs (windows, 3.0.6)	5m 30s
specs (windows, 3.1.4)	4m 9s
specs (windows, 3.2.2)	4m 10s
specs (windows, 3.3.0)	5m 13s
specs (ubuntu, 3.3.0, --enable-frozen-string-literal)	1m 22s
	31m 56s

Provide feedback