Nullable annotation added in constructor argument.

[soumyaPrakashB]

In one of the constructors of the AggregationOptions class, Nullable annotation is missing for an argument. This cursor parameter canbe null, however as it is not marked as Nullable, in some projects the sonar quality check is failing stating the reason "Nullness of parameters should be guaranteed."

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[christophstrobl]

Thank you @soumyaPrakashB!