Upgrade to GitHub-native Dependabot

[dependabot-preview]

Dependabot Preview will be shut down on August 3rd, 2021. In order to keep getting Dependabot updates, please merge this PR and migrate to GitHub-native Dependabot before then.

Dependabot has been fully integrated into GitHub, so you no longer have to install and manage a separate app. This pull request migrates your configuration from Dependabot.com to a config file, using the new syntax. When merged, we'll swap out dependabot-preview (me) for a new dependabot app, and you'll be all set!

With this change, you'll now use the Dependabot page in GitHub, rather than the Dependabot dashboard, to monitor your version updates, and you'll configure Dependabot through the new config file rather than a UI.

If you've got any questions or feedback for us, please let us know by creating an issue in the dependabot/dependabot-core repository.

Learn more about migrating to GitHub-native Dependabot

Please note that regular @dependabot commands do not work on this pull request.

[codecov]

Codecov Report

Merging #1314 (98eea0b) into main (a4bb2ab) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #1314   +/-   ##
=======================================
  Coverage   91.51%   91.51%           
=======================================
  Files          34       34           
  Lines        4255     4255           
=======================================
  Hits         3894     3894           
  Misses        361      361           

---

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 a4bb2ab...98eea0b. Read the comment docs.