Redis Server URI correct parsing

Including password support.
Code style
#6495 - Splitting tests: verifying smaller features of `Zend\Cache\Storage\Adapter\RedisResourceManager#setServer` and `#setResource`
#6495 - Cleaned up `Zend\Cache\Storage\Adapter\RedisResourceManager#setServer` and `#setResource` implementation
Merge branch 'hotfix/#6495-redis-server-uri-parsing'

Close #6495