(DOCSP) Adds missing comma to code example. (#268)

<!-- Add a description of your PR here (optional) -->

- [DOCSP-16762](https://jira.mongodb.org/browse/DOCS-16762)
-
[STAGING](https://preview-mongodberabilmdb.gatsbyjs.io/ops-manager/DOCSP-16762/reference/api/automation-config/automation-config-example/)

- [LATEST BUILD
LOG](https://workerpool-boxgs.mongodbstitch.com/pages/job.html?collName=queue&jobId=667c29bbebce19f31448837b)

### Self-Review Checklist

- [ ]
[Define](https://wiki.corp.mongodb.com/display/DE/Taxonomy+tagging+instructions)
taxonomy
[values](https://wiki.corp.mongodb.com/display/DE/Docs+Taxonomy) at top
of page.
- [ ] Add genre facets (tutorial or reference), as in this [example
PR](10gen/cloud-docs#5042).
- [ ] Add programmingLanguage (if necessary).
- [ ] Add meta keywords (if necessary).
- [ ] Resolve any new warnings or errors in the build.
- [ ] Proofread for spelling and grammatical errors.
- [ ] Check staging for rendering issues.
- [ ] Confirm links are working.

Author: erabil-mdb

source/reference/api/automation-config/automation-config-example.txt

@@ -157,7 +157,7 @@ place of some field values.
      "balancer" : { ... },
      "auth" : {
        "authoritativeSet" : false,
-       "disabled" : true
+       "disabled" : true,
        "usersDeleted" : [ ],
        "usersWanted" : [ ]
      },