Upgrade to GitHub-native Dependabot

.github/dependabot.yml

@@ -0,0 +1,42 @@
+version: 2
+updates:
+- package-ecosystem: npm
+  directory: "/"
+  schedule:
+    interval: daily
+    time: "03:00"
+  open-pull-requests-limit: 10
+  ignore:
+  - dependency-name: eslint
+    versions:
+    - 7.24.0
+  - dependency-name: ajv
+    versions:
+    - 7.1.0
+    - 7.2.1
+    - 7.2.3
+  - dependency-name: "@types/node"
+    versions:
+    - 14.14.24
+    - 14.14.26
+    - 14.14.28
+    - 14.14.32
+    - 14.14.33
+    - 14.14.34
+  - dependency-name: "@typescript-eslint/eslint-plugin"
+    versions:
+    - 4.15.0
+    - 4.17.0
+  - dependency-name: "@typescript-eslint/parser"
+    versions:
+    - 4.15.0
+    - 4.17.0
+  - dependency-name: "@types/koa"
+    versions:
+    - 2.11.8
+  - dependency-name: "@babel/preset-typescript"
+    versions:
+    - 7.12.16
+  - dependency-name: typescript
+    versions:
+    - 4.1.4