Add {cli} error messaging for assert_one_to_one()

[ddsjoberg]

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[github-actions]

Package	Line Rate	Health
admiraldev	95%	✔
Summary	95% (1077 / 1131)	✔

[bundfussr]

Tests need to be updated to expect class and snapshot. And a test checking that no error is issued if the specified variables are one to one should be added.