QuickCheck Arbitrary instances for Ledger types

[SeungheonOh]

Describe the feature you'd like

Currently, each projects need to write some property testing generator and shrinker on per-project biases, making testing not only more difficult but possibly more inconsistent and un-standardized. Quickcheck Arbirary instances for each types that PlutusLedgerApi exports would immensely help when testing scripts, generating some place-holder values, or even maintaining eDSL equivalent for ledger api--for example, Plutarch.

[effectfully]

That would be great to have indeed. I've brought it to the team and the team agreed.

I'm going to mark this issue as "low priority" though, since it's not a bug or similar.

PR would be very welcome.