[Tests][Bug] Fix staking status in generate_pos()
[Tests][Bug] Fix staking status in generate_pos()

"validtime" is not returned from getstakingstatus anymore (nor it was
needed).
PIVX-Project/PIVX,PIVX-Project/PIVX,Mrs-X/PIVX,Mrs-X/PIVX,Darknet-Crypto/Darknet,PIVX-Project/PIVX,Mrs-X/Darknet,Darknet-Crypto/Darknet,PIVX-Project/PIVX,Mrs-X/PIVX,Mrs-X/PIVX,PIVX-Project/PIVX,Mrs-X/PIVX,Darknet-Crypto/Darknet,Mrs-X/Darknet,Mrs-X/Darknet,Mrs-X/Darknet,Mrs-X/Darknet,Mrs-X/Darknet,PIVX-Project/PIVX,Darknet-Crypto/Darknet,Mrs-X/PIVX,Darknet-Crypto/Darknet,PIVX-Project/PIVX,Darknet-Crypto/Darknet,PIVX-Project/PIVX,PIVX-Project/PIVX