add dependabot (#16)

Author: martin-mfg

.github/dependabot.yml

@@ -0,0 +1,28 @@
+version: 2
+updates:
+  # Maintain dependencies for npm
+  - package-ecosystem: npm
+    directory: "/"
+    schedule:
+      interval: daily
+    open-pull-requests-limit: 20
+    commit-message:
+      prefix: "build(deps)"
+      prefix-development: "build(deps-dev)"
+    cooldown:
+      default-days: 7
+    ignore:
+      - dependency-name: "@types/node"
+        update-types: ["version-update:semver-major"]
+
+  # Maintain dependencies for GitHub Actions
+  - package-ecosystem: github-actions
+    directory: "/"
+    schedule:
+      interval: daily
+    open-pull-requests-limit: 20
+    commit-message:
+      prefix: "ci(deps)"
+      prefix-development: "ci(deps-dev)"
+    cooldown:
+      default-days: 7