fix: the turn down date for global batch uri

[bradvogel]

Fixes the date of when the global batch endpoint will be turned down, per the extension outlined in https://developers.googleblog.com/2018/03/discontinuing-support-for-json-rpc-and.html.

[googlebot]

Thanks for your pull request. It looks like this may be your first contribution to a Google open source project (if not, look below for help). Before we can look at your pull request, you'll need to sign a Contributor License Agreement (CLA).

📝 Please visit https://cla.developers.google.com/ to sign.

Once you've signed (or fixed any issues), please reply here with @googlebot I signed it! and we'll verify it.

---

What to do if you already signed the CLA

Individual signers

• It's possible we don't have your GitHub username or you're using a different email address on your commit. Check your existing CLA data and verify that your email is set on your git commits.

Corporate signers

• Your company has a Point of Contact who decides which employees are authorized to participate. Ask your POC to be added to the group of authorized contributors. If you don't know who your Point of Contact is, direct the Google project maintainer to go/cla#troubleshoot (Public version).
• The email used to register you as an authorized contributor must be the email used for the Git commit. Check your existing CLA data and verify that your email is set on your git commits.
• The email used to register you as an authorized contributor must also be attached to your GitHub account.

ℹ️ Googlers: Go here for more info.

[bradvogel]

@googlebot I signed it!

[googlebot]

CLAs look good, thanks!

ℹ️ Googlers: Go here for more info.

[gcf-merge-on-green]

Your PR has attempted to merge for 3 hours. Please check that all required checks have passed, you have an automerge label, and that all your reviewers have approved the PR

[gcf-merge-on-green]

Your PR has attempted to merge for 3 hours. Please check that all required checks have passed, you have an automerge label, and that all your reviewers have approved the PR

[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.

[bradvogel]

@busunkim96 anything you need from me to merge this?

[busunkim96]

@bradvogel Nope, just need to kick CI. Thanks for checking!