Update style guide with correct usage of MS SQL (#29829)

* Added correct usage of MS SQL

* Updated as per Diana's comment.

* Fixed wording.

* Update contribute/style-guides/documentation-style-guide.md

Co-authored-by: Diana Payton <52059945+oddlittlebird@users.noreply.github.com>

Co-authored-by: Diana Payton <52059945+oddlittlebird@users.noreply.github.com>

contribute/style-guides/documentation-style-guide.md

@@ -285,3 +285,8 @@ When referencing the Prometheus data source exporters, always use "node_exporter
 
 **Correct:** node_exporter, windows_exporter
 **Incorrect:** Node Exporter, node exporter, Windows Exporter, Windows exporter, windows exporter.
+
+### MS SQL Server
+Always use "MS SQL" when referring to MS SQL Server application. Do not use "MSSQL" unless you are specifically referring to a UI element that uses it.
+
+Incorrect UI spellings will be corrected in a later version of Grafana.