fix: tolerate endo pre and post #822

[erights]

Test was testing for error message before endojs/endo#822 , which is not yet part of an endo release. In anticipation, and to aid development against endo master using yarn link, temporarily make it tolerate both the old and new error messages.

Question for reviewers: To what degree should tests be testing for the content of error messages anyway?

[kriskowal]

I’m generally not fond of “change detector” tests. There should be a message test at least to be sure the error is related to the intended failure. A very small substring should suffice.