Upgrade to GitHub-native Dependabot

.github/dependabot.yml

@@ -0,0 +1,37 @@
+version: 2
+registries:
+  npm-registry-npm-pkg-github-com:
+    type: npm-registry
+    url: https://npm.pkg.github.com
+    token: "${{secrets.NPM_REGISTRY_NPM_PKG_GITHUB_COM_TOKEN}}"
+
+updates:
+- package-ecosystem: npm
+  directory: "/"
+  schedule:
+    interval: monthly
+  open-pull-requests-limit: 10
+  ignore:
+  - dependency-name: npm-check-updates
+    versions:
+    - 10.2.5
+    - 11.1.1
+  - dependency-name: ts-jest
+    versions:
+    - 26.4.4
+    - 26.5.0
+  - dependency-name: "@types/node"
+    versions:
+    - 14.14.17
+    - 14.14.22
+  - dependency-name: "@types/jest"
+    versions:
+    - 26.0.19
+  - dependency-name: lodash
+    versions:
+    - 4.17.20
+  - dependency-name: typescript
+    versions:
+    - 3.9.7
+  registries:
+  - npm-registry-npm-pkg-github-com