feat: Add deleteStep mutation

packages/backend/src/graphql/mutations/delete-step.ts

@@ -0,0 +1,33 @@
+import { GraphQLInt, GraphQLNonNull, GraphQLBoolean } from 'graphql';
+import Step from '../../models/step';
+import RequestWithCurrentUser from '../../types/express/request-with-current-user';
+
+type Params = {
+  id: number;
+};
+
+const deleteStepResolver = async (
+  params: Params,
+  req: RequestWithCurrentUser
+) => {
+  // TODO: This logic should be revised by using current user
+  await Step.query()
+    .delete()
+    .findOne({
+      id: params.id,
+    })
+    .throwIfNotFound();
+
+  return;
+};
+
+const deleteStep = {
+  type: GraphQLBoolean,
+  args: {
+    id: { type: GraphQLNonNull(GraphQLInt) },
+  },
+  resolve: (_: any, params: Params, req: RequestWithCurrentUser) =>
+    deleteStepResolver(params, req),
+};
+
+export default deleteStep;