Governance. Edit delegation for multishard - not optimal execution flow

[stepanLav]

Description

When user has delegations for multishard wallet and wants to edit it, always will be created the whole list of operations. For example, if I have 10 multishard accounts which are delegated to track 10 and I edit that delegations in order to add track 15 I would force to redelegate to track 10 which is quite big amount of fee on Polkadot

Steps to Reproduce

1. Add delegations for 10 accounts into multishard wallet for 1 track
2. Edit delegation in order to add new track delegation without changing an amount

Expected Behavior

Will be created only needed transactions (for new track)

Actual Behavior

Will be created 10x2 additional operations (undelegate, delegate)

Environment

0a49e33

[pgolovkin]

Work on it with next iteration of OpenGov delegation improvement for multishard.