*Motivation*

Trying to fix #3975

When a reset of a cursor is performed with some timestamp on a non-durable
consumer the message finder will fail with null pointer exception due to
`cursor.getName()` being null.

*Modifications*

  - Add method overloading for `newNonDurableCursor()` with subscription name.
  - Fix method getNonDurableSubscription to call `newNonDurableCursor()` with
    proper subscription name
  - Add test to assert issue.