chore: regenerate README

[yoshi-automation]

This PR was generated using Autosynth. 🌈

Log from Synthtool

2021-04-15 21:41:09,203 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-datastore/.github/readme/synth.py.
On branch autosynth-readme
nothing to commit, working tree clean
2021-04-15 21:41:10,444 synthtool [DEBUG] > Wrote metadata to .github/readme/synth.metadata/synth.metadata.

Full log will be available here:
https://source.cloud.google.com/results/invocations/27e279d2-d960-4474-a5d5-f5122234a196/targets

• To automatically regenerate this PR, check this box. (May take up to 24 hours.)

[codecov]

Codecov Report

Merging #396 (ee6c014) into master (c6e85eb) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #396   +/-   ##
=========================================
  Coverage     56.74%   56.74%           
  Complexity      384      384           
=========================================
  Files            48       48           
  Lines          2395     2395           
  Branches        265      265           
=========================================
  Hits           1359     1359           
  Misses          929      929           
  Partials        107      107           

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[yoshi-approver]

Rubber stamped PR!

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