Error in description

There is an error in "locked" argument description.
It actually returns <true> if session is locked by another request, not "if a lock is successfully obtained".

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#### Document Details

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* ID: f5d6d398-ec87-a2bf-206c-5bdaaafcc282
* Version Independent ID: 8a2afa44-2376-71d5-6ed9-0b1b22b0bdcc
* Content: [SessionStateStoreProviderBase.GetItemExclusive(HttpContext, String, Boolean, TimeSpan, Object, SessionStateActions) Method (System.Web.SessionState)](https://docs.microsoft.com/en-us/dotnet/api/system.web.sessionstate.sessionstatestoreproviderbase.getitemexclusive?redirectedfrom=MSDN&view=netframework-4.7.2#System_Web_SessionState_SessionStateStoreProviderBase_GetItemExclusive_System_Web_HttpContext_System_String_System_Boolean__System_TimeSpan__System_Object__System_Web_SessionState_SessionStateActions__)
* Content Source: [xml/System.Web.SessionState/SessionStateStoreProviderBase.xml](https://github.com/dotnet/dotnet-api-docs/blob/master/xml/System.Web.SessionState/SessionStateStoreProviderBase.xml)
* Product: **dotnet-api**
* GitHub Login: @dotnet-bot
* Microsoft Alias: **dotnetcontent**