ci: Add dependabot.yml (#51)

* ci: Add dependabot.yml

* Remove evergreen

Author: lachlancollins

.github/dependabot.yml

@@ -0,0 +1,11 @@
+version: 2
+
+updates:
+  - package-ecosystem: 'npm'
+    directory: '/'
+    schedule:
+      interval: 'weekly'
+  - package-ecosystem: 'github-actions'
+    directory: '/'
+    schedule:
+      interval: 'weekly'