Adding try_state hook for Tips pallet

[Doordashcon]

Part of #239.

Invariant

1. The number of entries in Tips should be equal to Reasons.
2. If OpenTip.finders_fee is true, then OpenTip.deposit should be greater than zero.
3. Reasons exists for each Tip[OpenTip.reason], implying equal length of storage.

polkadot address: 12zsKEDVcHpKEWb99iFt3xrTCQQXZMu477nJQsTBBrof5k2h

[ggwpez]

(We should not invest much effort into this pallet since it is Gov1)

Not sure if this is actually correct, since DataDepositPerByte and TipReportDepositBase can be configured to zero.
Maybe also add a check to the integrity_test that TipReportDepositBase is not zero since otherwise it does not take a deposit for the entry into the Reasons and Tips map.

Another invariant would be that the Reason for each Tips exists.

[Doordashcon]

@ggwpez Thanks for the review

(We should not invest much effort into this pallet since it is Gov1)

Noted

Not sure if this is actually correct, since DataDepositPerByte and TipReportDepositBase can be configured to zero.
Maybe also add a check to the integrity_test that TipReportDepositBase is not zero since otherwise it does not take a deposit for the entry into the Reasons and Tips map.

🤝 will include this.

Another invariant would be that the Reason for each Tips exists.

I previously included this as an Invariant here, seems like it's universal logic in the function calls and also tests for this would always pass.

[gpestana]

Added a couple of comments, but approving. thanks!

[ggwpez]

LGTM, lets get it merged soon. Its open since quite a while now 😅