build: Add dependabot config

.github/dependabot.yml

@@ -0,0 +1,11 @@
+version: 2
+updates:
+  - package-ecosystem: "pub"
+    directory: "/"
+    schedule:
+      interval: "daily"
+    allow:
+      - dependency-name: "*"
+    commit-message:
+      prefix: "build: "
+      include: "scope"