Migrate pallet-collective to the new pallet attribute macro

[koushiro]

Part of #7882

Migrate the pallet-collective to the new pallet attribute macro

diff council-before.json council-after.json:

4c4
<     "prefix": "Instance1Collective",
---
>     "prefix": "Council",

diff technical-committee-before.json technical-committee-after.json:

4c4
<     "prefix": "Instance2Collective",
---
>     "prefix": "TechnicalCommittee",

⚠️ Breaking Change ⚠️

From https://crates.parity.io/frame_support/attr.pallet.html#checking-upgrade-guidelines

storages now use PalletInfo for module_prefix instead of the one given to decl_storage: Thus any use of this pallet in construct_runtime! should be careful to update name in order not to break storage or to upgrade storage (moreover for instantiable pallet). If pallet is published, make sure to warn about this breaking change.

So users of the pallet must be careful about the name they used in construct_runtime!. Hence the runtime-migration label, which might not be needed depending on the configuration of the pallet.

polkadot and kusama use Counciland TechnicalCommittee as pallet name, but the current module prefix is Instance1Collective and Instance2Collective respectively , thus need to migrate the storages.

---

polkadot companion: paritytech/polkadot#3265

[koushiro]

@shawntabrizi @thiolliere PTAL

[gui1117]

looks good to me,

I tested the migration with try-runtime on polkadot block 6,163,183

[gui1117]

to check all the empty emptyness or that there is only key after a prefix I think we can use https://paritytech.github.io/substrate/frame_support/storage/migration/fn.storage_iter.html

EDIT: sorry I talk to fast, it only works for storages.

EDIT EDIT: maybe this can be used: https://paritytech.github.io/substrate/frame_support/storage/struct.PrefixIterator.html

[gui1117]

I think the migration should look like this: #9746
Or maybe we can even remove some assert which can lead to false positive (like asserting some key has been moved).

[gui1117]

I think the migration checks are not very accurate, I think it should be improved similarly to this #9746

Once this is done, I'll do the try-runtime on polkadot/kusama and approve

[gui1117]

looks good to me

[gui1117]

the CI has failed due to some flacky test, but AFAIK some fix are ongoing. I tried to test the companion with try-runtime on polkadot and kusama and it was successful. I think we can merge once we solve our CI issue.

[gui1117]

bot merge

[ghost]

Trying merge.