SqlScriptPublishModel fires ScriptItemsCollected event with duplicate URNs

When using SqlScriptPublishModel.SelectedObjects to provide URNs of objects to script, the application may have constructed the URN manually with user input.
During scripting, the URNs used to populate progress events are generated by SMO based on server and database queries. As a result the Server[@Name='myserver'] component of the output URN may be of a different case than that of the input URN, causing some internal dictionary lookups based on URN keys to fail. Applications will see this in the ScriptItemsCollected event where the ScriptItemsArgs.Urns collection may have multiple instances of the URN, differing only by the case of the server name component.

We found this in a sql tools service test case failure when the server name case in the local settings json file mismatches the server's self-reported name.

从 SqlScriptPublishModel.SelectedObjects 和 ScriptItemsCollected 事件开始，然后使用 issue 中链接的 SqlScriptPublishModelTests.cs 测试用例重现该故障。当服务器名称的大小写不同时，ScriptItemsArgs.Urns 集合不包含仅大小写不同的重复 URN，即表示完成。