Add script to diff zjit stats from output csv #1685

Job	Run time
benchmark-graph	53s
benchmark-ractor (head)	6m 44s
benchmark-run-once	1m 36s
benchmark-default (head)	13m 4s
benchmark-default (truffleruby, --excludes=knucleotide,lobsters,ruby-lsp,shipit)	13m 3s
test (ruby)	55s
test (head)	48s
benchmark-ractor-only (head)	40s
benchmark-default (ruby)	13m 39s
test (truffleruby)	1m 53s
all-tests	4s
	53m 19s

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