chore: mini nits from ics29 audit

[seantking]

Description

There is a call for adding a var declaration in the issue as well but I wasn't sure of the reasoning.

closes: #1325

---

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[crodriguezvega]

I left some nits of these nits... :)

The reasoning to do var declaration here was to just be consistent with the rest of the codebase.

[colin-axner]

LGTM, it'd be great if you could add the var declaration as well

[colin-axner]

I think we should log the first failed distribution. I think it is very unlikely refunding the fee fails, but trying to distribute to a relayer could definitely fail. It'd be useful for that relayer to notice and see that the fee got refunded after the failed distribution

[damiannolan]

Agree with @colin-axner re. moving logging up one level of scope.

About the var declaration, it's misleading in the issue and linked code because of recent changes. The code to be changed is the ack initialisation here.

Removing the new() func and using the var declaration

ack := new(types.IncentivizedAcknowledgement)
if err := types.ModuleCdc.UnmarshalJSON(acknowledgement, ack); err != nil {
	return sdkerrors.Wrapf(err, "cannot unmarshal ICS-29 incentivized packet acknowledgement: %v", ack)
}