fix: prevent unhandled rejections by avoid .catch

[JustinBeckwith]

Resolves #403

[codecov-io]

Codecov Report

Merging #404 into master will increase coverage by 0.18%.
The diff coverage is 69.44%.

@@            Coverage Diff             @@
##           master     #404      +/-   ##
==========================================
+ Coverage   94.89%   95.07%   +0.18%     
==========================================
  Files          15       15              
  Lines         960      955       -5     
  Branches      218      217       -1     
==========================================
- Hits          911      908       -3     
+ Misses         49       47       -2

Impacted Files	Coverage Δ
src/auth/googleauth.ts	94.66% <0%> (ø)	⬆️
src/auth/jwtclient.ts	94.84% <100%> (ø)	⬆️
src/transporters.ts	95.91% <100%> (ø)	⬆️
src/auth/jwtaccess.ts	98.11% <100%> (ø)	⬆️
src/auth/refreshclient.ts	90.69% <100%> (ø)	⬆️
src/auth/oauth2client.ts	94.94% <78.26%> (+0.57%)	⬆️

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