chore: regenerate README

[yoshi-automation]

This PR was generated using Autosynth. 🌈

Log from Synthtool

2021-03-10 19:56:00,267 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-bigquerydatatransfer/.github/readme/synth.py.
On branch autosynth-readme
nothing to commit, working tree clean
2021-03-10 19:56:01,251 synthtool [DEBUG] > Wrote metadata to .github/readme/synth.metadata/synth.metadata.

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[yoshi-approver]

Rubber stamped PR!

[codecov]

Codecov Report

Merging #688 (7aef91a) into master (6b10b97) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #688   +/-   ##
=========================================
  Coverage     80.46%   80.46%           
  Complexity      132      132           
=========================================
  Files             7        7           
  Lines           952      952           
  Branches         18       18           
=========================================
  Hits            766      766           
  Misses          163      163           
  Partials         23       23           

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