[next] NcDateTimePicker popover too small

[raimund-schluessler]

The popover of NcDateTimePicker is to small on the next branch, the right side buttons overflow the parent container.

This happens, because of this rule.

.mx-date-time {
  position: relative;
  width: 248px;
  height: 270px
}

Adding

.mx-date-time {
  width: unset;
}

would fix it, but I don't know whether this would have side-effects.