Bug 32335: Allow stock rotation items to be advanced when in transit

Bug 32335: Allow stock rotation items to be advanced when in transit

This patch adjusts the logic so that we check:
1 - If there are less than 2 stages we disable the 'Move to next stage' button
2 - If the item is not in transit, we show move to next normally
3 - If the item is in transit (and there is more than 1 stage) the button is enabled with a note about transfer

To test:
1 - Setup a rota with multiple stages
2 - Add an item
3 - Advance to next stage
4 - Observe 'Move to next stage' button is disabled
5 - Check item in at destination
6 - Reload rota - observe 'Move to next stage' is enabled
7 - Apply patch
8 - Click 'Move to next stage'
9 - Note button is not disabled
10 - Hover and confirm note about transit
11 - Click 'Move to next stage'
12 - Checkin item at wrong branch, confirm it is correctly directed to correct stage

Signed-off-by: Sam Lau <samalau@gmail.com>
Signed-off-by: Pedro Amorim <pedro.amorim@ptfs-europe.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>