[TASK] NEWS.txt Entry for recursive validation in extbase

This patch adds an entry to NEWS.txt for the following TYPO3 extbase
patch:

- Backport recursive and allowing empty validation from Flow
  https://review.typo3.org/#/c/21428/

Releases: 6.2
Resolves: #49669
Change-Id: I658245e34e3d2b6e638111c5d4a5e0242bdcc6e2
Reviewed-on: https://review.typo3.org/21885
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn
Reviewed-by: Anja Leichsenring
Tested-by: Anja Leichsenring