Add SQL query for MSSQL to migration documentation for Jira Cloud to Jira Server

Issue Summary

From https://confluence.atlassian.com/adminjiraserver/migrating-from-jira-cloud-to-server-applications-938846963.html , Migrating from Jira Cloud to Jira Server / Data Center requires running SQL queries. We provide queries for Postgres and MySQL but not for MSSQL.

Ideally we would add the MS SQL query below to the migration documentation above.

This is reproducible on Data Center: Yes

Steps to Reproduce

1. Setup Jira Data Center with MSSQL
2. Export Jira Cloud data
3. Attempt to import Jira Cloud data into Jira Data Center

Expected Results

A query for MS SQL is provided, being a supported database

Actual Results

A query for MS SQL database is not provided

Workaround

The MS SQL query below has been tested to work for the migration steps outlined above:

select (((((('UPDATE jiraschema.jiraaction SET actionbody =  CAST(REPLACE(CAST(actionbody as NVarchar(MAX)), ''accountid:' + cast(cu.external_id as varchar(max))) + ''', ''') + cast(cu.lower_user_name as varchar(max))) + ''') AS NText) WHERE actionbody LIKE ''%[[]~accountid:') + cast(cu.external_id as varchar(max))) + ']%'';') [Queries to fix]
from jiraschema.cwd_user cu
where cu.external_id is not null