* Remove .NET Core 3.1 support and standardize on .NET 6
Signed-off-by: Yash Nisar <yashnisar@microsoft.com>
* Remove support for .NET 5 as well
Signed-off-by: Yash Nisar <yashnisar@microsoft.com>
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Signed-off-by: Yash Nisar <yashnisar@microsoft.com>