Add Dependabot

Author: LouisMT

.github/dependabot.yaml

@@ -0,0 +1,14 @@
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+  - package-ecosystem: "dotnet-sdk"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+  - package-ecosystem: "nuget"
+    directory: "/src/Core"
+    schedule:
+      interval: "weekly"

global.json

@@ -0,0 +1,6 @@
+{
+  "sdk": {
+    "version": "9.0.0",
+    "rollForward": "latestFeature"
+  }
+}