[DV] Remove urandom from task port
[DV] Remove urandom from task port

Remove `$urandom()` calls from a task port to work around missing
functionality in Aldec Riviera-Pro 2019.10.

Signed-off-by: Dawid Zimonczyk <049f7e3b2b9716e0f331e21b3c38cae5a47562b7@aldec.com.pl>

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