Server.IsTraceFlagOn returns true for session scope flags when isGlobalTraceFlag param is true

Repro:

server.SetTraceFlag(1800, isOn: true);
var isOn = server.IsTraceFlagOn(1800, isGlobalTraceFlag: true);
// isOn is "true"

dbcc tracestatus() shows this:

TraceFlag Status Global Session
 
124       1      1      0
1800      1      0      1
4631      1      1      0
11100     1      1      0

I filed a doc bug at https://github.com/MicrosoftDocs/sql-docs/issues/4920 because it seems tracestatus() and tracestatus(-1) return the same table, even though (-1) is only supposed to return global flags according to the current docs. I think the SMO code was relying on that difference.

首先使用标志 1800，通过 Server.SetTraceFlag、Server.IsTraceFlagOn 和 DBCC tracestatus() 重现该问题。比较全局范围与会话范围的 API 结果，并检查关联的 SQL 文档问题；当 IsTraceFlagOn 报告的范围与预期的全局标志行为一致时，即表示完成。