deps: update dependency com.google.protobuf:protobuf-java to v3.12.2

[renovate-bot]

This PR contains the following updates:

Package	Update	Change
com.google.protobuf:protobuf-java	patch	3.12.0 -> 3.12.2

---

Renovate configuration

📅 Schedule: At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻️ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

---

• If you want to rebase/retry this PR, check this box

---

This PR has been generated by WhiteSource Renovate. View repository job log here.

[codecov]

Codecov Report

Merging #67 into master will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master      #67   +/-   ##
=========================================
  Coverage     75.25%   75.25%           
  Complexity      155      155           
=========================================
  Files            12       12           
  Lines          1184     1184           
  Branches         11       11           
=========================================
  Hits            891      891           
  Misses          270      270           
  Partials         23       23           

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 2fe087f...debc3cd. Read the comment docs.

[gcf-merge-on-green]

Merge-on-green attempted to merge your PR for 6 hours, but it was not mergeable because either one of your required status checks failed, or one of your required reviews was not approved. Learn more about your required status checks here: https://help.github.com/en/github/administering-a-repository/enabling-required-status-checks. You can remove and reapply the label to re-run the bot.

[gcf-merge-on-green]

Merge-on-green attempted to merge your PR for 6 hours, but it was not mergeable because either one of your required status checks failed, or one of your required reviews was not approved. Learn more about your required status checks here: https://help.github.com/en/github/administering-a-repository/enabling-required-status-checks. You can remove and reapply the label to re-run the bot.

[gcf-merge-on-green]

Merge-on-green attempted to merge your PR for 6 hours, but it was not mergeable because either one of your required status checks failed, or one of your required reviews was not approved. Learn more about your required status checks here: https://help.github.com/en/github/administering-a-repository/enabling-required-status-checks. You can remove and reapply the label to re-run the bot.