CASSNDRA-18780 Fixed ConnectionBurnTest fails with NullPointerException

[Mmuzaf]

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[Mmuzaf]

@belliottsmith I've addressed your comments, please, take a look again :-)

[Mmuzaf]

@belliottsmith Hi Benedict, have you had a chance to look at the comments that have been fixed? :-)

[Mmuzaf]

@belliottsmith Hi Benedict, I think we are really close to fixing it! :-) Would you mind taking one last look?