[TM-303] Transfer 0 mutez in `lCall`

Description

Problem: current lCall is only useful when you don't care about transferred amount because it's pretty arbitrary. However, sometimes we want to transfer exactly 0 mutez and don't care about source (or use withSender if we care). It's definitely more common than desire to transfer exactly 1000 mutez.

Solution: transfer 0 in lCall.

Related issue(s)

https://issues.serokell.io/issue/TM-303

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