Examples fix: Support preflight of auth libraries in js

[GhiaC]

No description provided.

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[GhiaC]

I signed it!

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[codecov-io]

Codecov Report

Merging #973 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #973   +/-   ##
=======================================
  Coverage   53.25%   53.25%           
=======================================
  Files          40       40           
  Lines        4007     4007           
=======================================
  Hits         2134     2134           
  Misses       1675     1675           
  Partials      198      198

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[GhiaC]

recheck

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[googlebot]

CLAs look good, thanks!

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[johanbrandhorst]

Thanks for the contribution!