It should not be possible to purchase 0 x CI Minutes

Problem

There are reports(internal link) of customers being able to purchase 0 x CI Minutes. Such purchases are found to have a value of 0.5 (which is probably later rounded up). The reason is that the application only checks for quantity > 0.

Proposed solution

The frontend should change this line to be quantity >= 1 instead. Considering checking that the value is a natural number (i.e. that is an integer Number.isInteger() and greater than or equal to 1) so that all values with a comma are excluded.

It will require 1 MR. (Note that the component is shared between CI Minutes and Storage.)

Description	MR
Update check on min quantity for CI Minutes	!105676 (merged)
Storage Purchase, avoid server call when invalid quantity	!105799 (merged)

Additional considerations

We might want to:

1. The copy says Enter a number greater than 0 (which entails 0.5 is a valid value). Maybe it should be updated to reflect the actual constraint
2. CustomersDot should not allow purchases with 0 value (the system is also probably rounding 0.5 to 0). Maybe we introduce validation on that side too