Upgrade to GitHub-native Dependabot (#720)

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Author: dependabot-preview[bot]

.github/dependabot.yml

@@ -0,0 +1,21 @@
+version: 2
+updates:
+- package-ecosystem: npm
+  directory: "/"
+  schedule:
+    interval: monthly
+  open-pull-requests-limit: 10
+  ignore:
+  - dependency-name: react-native
+    versions:
+    - 0.64.0-rc.3
+  - dependency-name: "@babel/preset-env"
+    versions:
+    - 7.13.8
+  - dependency-name: flow-bin
+    versions:
+    - 0.143.1
+    - 0.145.0
+  - dependency-name: "@types/react-native"
+    versions:
+    - 0.63.43