Have dependabot keep our dependencies up to date.

.github/dependabot.yml

@@ -0,0 +1,21 @@
+# Please see the documentation for all configuration options:
+# https://docs.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
+
+version: 2
+updates:
+  - package-ecosystem: "npm"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+    versioning-strategy: increase
+    groups:
+      minor-updates:
+        patterns: ["*"]
+        update-types: [patch, minor]
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+    groups:
+      actions-org:
+        patterns: ["actions/*"]