## Description 

Adding proptest for gas smashing.
Coin objects always coming from genesis makes the scenario not as real
as it could and should be. But the fix is for another day

## Test Plan 

This is it

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### Type of Change (Check all that apply)

- [ ] user-visible impact
- [ ] breaking change for a client SDKs
- [ ] breaking change for FNs (FN binary must upgrade)
- [ ] breaking change for validators or node operators (must upgrade
binaries)
- [ ] breaking change for on-chain data layout
- [ ] necessitate either a data wipe or data migration

### Release notes