Add new benchmark for getivar with T_CLASS and T_MODULE #1540

Job	Run time
test (truffleruby)	49s
benchmark-default (truffleruby)	11m 55s
test (head)	54s
benchmark-default (head)	11m 16s
benchmark-ractor (head)	12m 28s
test (ruby)	55s
benchmark-default (ruby)	11m 6s
benchmark-ractor-only (head)	49s
benchmark-ractor-only (ruby)	56s
benchmark-ractor (ruby)	13m 31s
benchmark-graph	49s
benchmark-run-once	1m 25s
all-tests	4s
	1h 6m 57s

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