(DOCSP-43613) Note that javascriptEnabled is deprecated and defaults to false (#377)

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Same change as 10gen/docs-cloud-manager#108 but
for Ops Manager (already LGTM'd)
- [DOCSP-43613](https://jira.mongodb.org/browse/DOCSP-43613)
-
[STAGING](https://deploy-preview-377--10gen-docs-ops-manager.netlify.app/reference/deployment-advanced-options/)

### 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: davidhou17

source/reference/deployment-advanced-options.txt

@@ -218,7 +218,13 @@ Security
      - :setting:`security.encryptionCipherMode`
    * - encryptionKeyFile
      - :setting:`security.encryptionKeyFile`
-   * - javascriptEnabled
+   * - javascriptEnabled 
+
+       .. note::
+
+          This setting is deprecated and will be removed 
+          in a future release. Defaults to ``false``.
+
      - :setting:`security.javascriptEnabled`
    * - kmipClientCertificateFile
      - :setting:`security.kmip.clientCertificateFile`