Broaden a test to cover an additional possible error message

[DilumAluthge]

I'm not sure when this error message changed, but it did, and we never updated this test.

Seen in PkgEval: https://s3.amazonaws.com/julialang-reports/nanosoldier/pkgeval/by_hash/df86fe4_vs_95f30e5/report.html

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 75.98%. Comparing base (39e7f8a) to head (c1a9470).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #284      +/-   ##
==========================================
+ Coverage   74.89%   75.98%   +1.08%     
==========================================
  Files          12       12              
  Lines         705      712       +7     
==========================================
+ Hits          528      541      +13     
+ Misses        177      171       -6     

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