hopli: Change HOPR allowance for the Safe

[Jaguaras]

Is your feature related to a problem?

Creating a rotsee node identity, initial allowance balance is quite small, during testing when opening and closing channels the allowance reduces quite quickly.

Describe the feature you'd like

To have ability to increase HOPR allowance for Rotsee safe.

[tolbrino]

@Jaguaras This should already be possible via the hub. Do you any other more specific requirements in mind?