Upgrade to GitHub-native Dependabot

Author: dependabot-preview[bot]

.github/dependabot.yml

@@ -0,0 +1,23 @@
+version: 2
+updates:
+- package-ecosystem: pip
+  directory: "/"
+  schedule:
+    interval: daily
+    time: "00:00"
+    timezone: Europe/Paris
+  open-pull-requests-limit: 2
+  reviewers:
+  - Morendil
+  - fpagnoux
+  - sandcha
+  - maukoquiroga
+  labels:
+  - kind:improvement
+  ignore:
+  - dependency-name: flake8-bugbear
+    versions:
+    - ">= 20.1.1.a, < 20.1.2"
+  - dependency-name: numpy
+    versions:
+    - ">= 1.18.a, < 1.19"