.github/settings.yml: switch to buildbot for required check

.github/settings.yml

@@ -144,8 +144,7 @@ branches:
         strict: false
         # Required. The list of status checks to require in order to merge into this branch
         contexts:
-          - ci/hercules/evaluation
-          - ci/hercules/onPush/default
+          - buildbot/nix-eval
       # Required. Enforce all configured restrictions for administrators. Set to true to enforce required status checks for repository administrators. Set to null to disable.
       enforce_admins: true
       # Disabled for bors to work