Stake distribution updates seem to take 4 epochs to reach ratification only for SPO votes

[aniketd]

In #4097 , there is a test that demonstrates that, for SPO votes, stake distribution updates (by adding UTxOs) as well as updates to the rewards, take 4 epochs to reach ratification, as opposed to 2 epochs for DRep votes.

• Investigate why there is a difference in the number of epochs needed to ratify
• Either document that this is expected behavior for the future or fix it.

[lehins]

Either document that this is expected behavior for the future or fix it.

This is not expected behavior.

Fix is implemented in #4115
Turns out we were using too old of stake distribution