feat: Add deleteStep mutation

packages/backend/src/graphql/root-mutation.ts

@@ -8,6 +8,7 @@ import deleteConnection from './mutations/delete-connection';
 import createFlow from './mutations/create-flow';
 import updateFlow from './mutations/update-flow';
 import createStep from './mutations/create-step';
+import deleteStep from './mutations/delete-step';
 import updateStep from './mutations/update-step';
 import executeStep from './mutations/execute-step';
 import login from './mutations/login';
@@ -25,9 +26,10 @@ const rootMutation = new GraphQLObjectType({
     updateFlow,
     createStep,
     updateStep,
+    deleteStep,
     executeStep,
-    login
-  }
+    login,
+  },
 });
 
 export default rootMutation;