Add package versions to required dependencies

Add specific package versions for required dependencies:
redis==3.5.3 and hiredis==2.0.0.
The reason for adding specific package versions is that sdlpy needs
redis 'compat' module but this module has been deprecated in newer
redis client 4.x.y versions and hence sdlpy is not compatible with
newer redis client versions.

Issue-Id: RIC-859

Signed-off-by: Timo Tietavainen <timo.tietavainen@nokia.com>
Change-Id: Ie3492314c82c5ed99f7d55db17c8161d41f6ac40