Stronger wording needed

Documentation states:
The cancellation token can be used...

Should instead say
The cancelation token will be used... since passing null will result in an exception (looks like it from the first look at https://referencesource.microsoft.com/#System.Data/System/Data/SqlClient/SqlDataReader.cs,f3a8ec4442971b00,references)

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#### Document Details

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* ID: f2e14e9c-856f-e965-9cb0-2bd9ff7df919
* Version Independent ID: 446389f6-2dd7-9cba-65a1-58f11470499b
* Content: [SqlDataReader.ReadAsync(CancellationToken) Method (System.Data.SqlClient)](https://docs.microsoft.com/en-us/dotnet/api/system.data.sqlclient.sqldatareader.readasync?view=netframework-4.7.2)
* Content Source: [xml/System.Data.SqlClient/SqlDataReader.xml](https://github.com/dotnet/dotnet-api-docs/blob/master/xml/System.Data.SqlClient/SqlDataReader.xml)
* Product: **dotnet-api**
* GitHub Login: @douglaslMS
* Microsoft Alias: **douglasl**