Merge pull request #627 from just-the-docs/dependabot/add-v2-config-file

Upgrade to GitHub-native Dependabot

.github/dependabot.yml

+version: 2
+updates:
+- package-ecosystem: npm
+  directory: "/"
+  schedule:
+    interval: daily
+    time: "10:00"
+  open-pull-requests-limit: 10
+- package-ecosystem: bundler
+  directory: "/"
+  schedule:
+    interval: daily
+    time: "10:00"
+  open-pull-requests-limit: 10