chore: dependabot (#9)

Author: rswanson

.github/dependabot.yml

@@ -0,0 +1,13 @@
+version: 2
+updates:
+- package-ecosystem: "cargo"
+  # Look for `Cargo.toml` and `Cargo.lock` in the root directory
+  directory: "/"
+  # Check for updates every Monday
+  schedule:
+    interval: "weekly"
+- package-ecosystem: "github-actions"
+  directory: "/"
+  # Check for updates every Monday
+  schedule:
+    interval: "weekly"