ci: fix dependabot config

Signed-off-by: Emilien Escalle <[email protected]>

Author: neilime

.github/dependabot.yml

@@ -28,7 +28,6 @@ updates:
 
   - package-ecosystem: "devcontainers"
     open-pull-requests-limit: 20
-    directory: "/"
     schedule:
       interval: weekly
       day: friday