examples/ct: use helper function for chain compare
examples/ct: use helper function for chain compare

google/trillian,RJPercival/trillian,gdbelvin/trillian,google/trillian,codingllama/trillian,Martin2112/trillian,AlCutter/trillian,gdbelvin/trillian,AlCutter/trillian,gtank/trillian,gdbelvin/trillian,daviddrysdale/trillian,Martin2112/trillian,daviddrysdale/trillian,Martin2112/trillian,codingllama/trillian,daviddrysdale/trillian,gtank/trillian,RJPercival/trillian