chore(dependabot): update NuGet directory for package updates

- Changes the directory in the Dependabot configuration to `/src` to correctly target the source folder for NuGet package updates.
- Ensures that dependency updates are focused on the appropriate application code path.

Author: winromulus

.github/dependabot.yml

@@ -5,7 +5,7 @@ registries:
     url: https://api.nuget.org/v3/index.json
 updates:
   - package-ecosystem: nuget
-    directory: "/"
+    directory: "/src"
     registries:
       - public-nuget
     schedule: