Attempt to fix a unit test that always failed on my laptop

[cfryanr]

Try to make the GCP plugin config less sensitive to the setup of the computer on which it runs.

Release note:

NONE

[codecov]

Codecov Report

Merging #893 (e445400) into main (5a1de2f) will increase coverage by 0.02%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main     #893      +/-   ##
==========================================
+ Coverage   78.96%   78.99%   +0.02%     
==========================================
  Files         132      132              
  Lines        9510     9510              
==========================================
+ Hits         7510     7512       +2     
+ Misses       1747     1745       -2     
  Partials      253      253              

Impacted Files	Coverage Δ
...l/localuserauthenticator/localuserauthenticator.go	57.20% <0.00%> (+0.93%)	⬆️

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