fix: export v1 and v1beta1 client class types correctly

[MarcPorciuncula]

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Fixes #1444 🦕

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[MarcPorciuncula]

@googlebot I signed it!

[codecov]

Codecov Report

Merging #1445 (932df92) into master (7d2a383) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1445   +/-   ##
=======================================
  Coverage   98.20%   98.20%           
=======================================
  Files          32       32           
  Lines       19507    19507           
  Branches     1363     1363           
=======================================
  Hits        19157    19157           
  Misses        346      346           
  Partials        4        4           

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[thebrianchen]

@MarcPorciuncula Thanks for catching this and filing a PR :) Much appreciated!