feat(ADR-006): POAP v2 (#195)

## Description

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files that
are the most critical to review. -->

This PR updates the POAP contract to make it compliant with the ADR-006.

Closes: #182
Closes: #183
Closes: #184 
Closes: #185 
Closes: #186 
Closes: #187 
Closes: #188 
Closes: #189

---

### Author Checklist

*All items are required. Please add a note to the item if the item is
not applicable and
please add links to any relevant follow up issues.*

I have...

- [x] included the correct [type
prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json)
in the PR title
- [ ] added `!` to the type prefix if API or client breaking change
- [x] targeted the correct branch (see [PR
Targeting](https://github.com/desmos-labs/desmos-contracts/blob/master/CONTRIBUTING.md#pr-targeting))
- [ ] provided a link to the relevant issue or specification
- [x] included the necessary unit and integration
[tests](https://github.com/desmos-labs/desmos-contracts/blob/master/CONTRIBUTING.md#testing)
- [ ] added a changelog entry to `CHANGELOG.md`
- [ ] updated the relevant documentation or specification
- [ ] reviewed "Files changed" and left comments if necessary
- [ ] confirmed all CI checks have passed

### Reviewers Checklist

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and please add
your handle next to the items reviewed if you only reviewed selected
items.*

I have...

- [ ] confirmed the correct [type
prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json)
in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
- [ ] confirmed all author checklist items have been addressed
- [ ] reviewed contract logic
- [ ] reviewed contract security
- [ ] reviewed API design and naming
- [ ] reviewed documentation is accurate
- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)

---------

Co-authored-by: Riccardo Montagnin <[email protected]>

.github/workflows/lint.yml

@@ -46,6 +46,7 @@ jobs:
         if: env.GIT_DIFF
         uses: actions-rs/[email protected]
         with:
+          version: '0.22.0'
           args: '--avoid-cfg-tarpaulin'
 
       - name: Upload coverage 📤