Update to expect_identical from expect_equal

[ShiyuC]

This PR closes #103

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[github-actions]

Package	Line Rate	Health
sdtm.oak	93%	✔
Summary	93% (952 / 1019)	✔

[ShiyuC]

@edgar-manukyan @rammprasad @muzzama-1990 I need one more approval for this PR if anyone has a minute. Thanks!