chore: Remove over-usage of invariant (#3719)

server/commands/documentCreator.ts

@@ -1,4 +1,3 @@
-import invariant from "invariant";
 import { Transaction } from "sequelize";
 import { Document, Event, User } from "@server/models";
 
@@ -105,14 +104,12 @@ export default async function documentCreator({
   // reload to get all of the data needed to present (user, collection etc)
   // we need to specify publishedAt to bypass default scope that only returns
   // published documents
-  const doc = await Document.findOne({
+  return await Document.findOne({
     where: {
       id: document.id,
       publishedAt: document.publishedAt,
     },
+    rejectOnEmpty: true,
     transaction,
   });
-  invariant(doc, "Document must exist");
-
-  return doc;
 }