Update dependabot.yml to remove Docker updates

Removed Docker updates from Dependabot configuration.

Author: gounthar

.github/dependabot.yml

@@ -9,7 +9,3 @@ updates:
     directory: "/" # Location of package manifests
     schedule:
       interval: "weekly"
-  - package-ecosystem: "docker"
-    directory: "/" # Location of .gitpod.yml
-    schedule:
-      interval: "weekly"