Null reference exception when an event handler for SqlConnection's InfoMessage is added and the FireInfoMessageEventOnUserErrors property is set to true

[onethoughtman]

Describe the bug

Using Microsoft.Data.SqlClient 5.2.0, executing a query on a connection with an InfoMessage event handler and the FireInfoMessageEventOnUserErrors property set to true results in an immediate NullReferenceException being thrown.

Exception message:
Object reference not set to an instance of an object.
Stack trace:
System.NullReferenceException: Object reference not set to an instance of an object.
    at Microsoft.Data.SqlClient.SqlCommand.GetCurrentBatchCommand()
   at Microsoft.Data.SqlClient.TdsParser.FireInfoMessageEvent(SqlConnection connection, SqlCommand command, TdsParserStateObject stateObj, SqlError error)
   at Microsoft.Data.SqlClient.TdsParser.TryRun(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj, Boolean& dataReady)
   at Microsoft.Data.SqlClient.SqlCommand.RunExecuteNonQueryTds(String methodName, Boolean isAsync, Int32 timeout, Boolean asyncWrite)
   at Microsoft.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(TaskCompletionSource`1 completion, Boolean sendToPipe, Int32 timeout, Boolean& usedCache, Boolean asyncWrite, Boolean inRetry, String methodName)
   at Microsoft.Data.SqlClient.SqlCommand.ExecuteNonQuery()

To reproduce

using (SqlConnection connection = new SqlConnection(connectionString))
{
    connection.InfoMessage += (sender, e) =>
    {
        foreach (SqlError error in e.Errors)
        {
            Console.WriteLine("Received from SQL Server: " + error.Message);
        }
    };

    connection.FireInfoMessageEventOnUserErrors = true;

    try
    {
        connection.Open();
        
        using (SqlCommand command = new SqlCommand())
        {
            command.Connection = connection;
            command.CommandType = CommandType.Text;

            command.CommandText = @"
                PRINT 'Starting process...';
                PRINT 'This is an informational message.';
                SELECT 1/0; 
                PRINT 'Ending process...';";

            command.ExecuteNonQuery();
        }
    }
    catch (SqlException ex)
    {
        Console.WriteLine("SQL Exception: " + ex.Message);
    }
}

Expected behavior

Received from SQL Server: Starting process...
Received from SQL Server: This is an informational message.
Received from SQL Server: Divide by zero error encountered.
Received from SQL Server: Ending process...

Further technical details

Microsoft.Data.SqlClient version: 5.2.0
.NET target: .NET 6
SQL Server version: SQL Server 2019 (RTM-CU25)
Operating system: Windows 10

Additional context
When I tried executing the same exact code on version 5.1.4, I get the expected behavior.

[JRahnama]

@onethoughtman this issue is addressed by PR #2399.

Closing as a duplicate of #2388