Fix SKE cluster maintenance updated outside TF causing error

[joaopalet]

• The API response always contains a mock date part in front of the time, so in case these are the same we just keep the current value in state (this part hasn't changed)
• What I changed was that now if the API response is different (not only in format but also in the actual time), this takes precedent over the state value as usual (instead of erroring)