Fix typo in Dependabot

Author: LouisMT

.github/dependabot.yaml

@@ -4,7 +4,7 @@ updates:
     directory: "/.github/workflows"
     schedule:
       interval: "weekly"
-  - package-ecosystem: "devcontainer"
+  - package-ecosystem: "devcontainers"
     directory: "/.devcontainer"
     schedule:
       interval: "weekly"