feat(ecocredit): add cancel sell-order command

[aleem1314]

Description

Closes: #1273

---

Author Checklist

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Reviewers Checklist

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• confirmed the correct type prefix in the PR title
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• reviewed state machine logic
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[codecov]

Codecov Report

Merging #1274 (3a828ef) into master (2e1b6ec) will increase coverage by 2.58%.
The diff coverage is 93.44%.

❗ Current head 3a828ef differs from pull request most recent head 13446e3. Consider uploading reports for the commit 13446e3 to get more accurate results

@@            Coverage Diff             @@
##           master    #1274      +/-   ##
==========================================
+ Coverage   77.48%   80.07%   +2.58%     
==========================================
  Files         213      235      +22     
  Lines       16094    21790    +5696     
==========================================
+ Hits        12471    17449    +4978     
- Misses       2627     3026     +399     
- Partials      996     1315     +319     

Flag	Coverage Δ
experimental-codecov	80.13% <93.44%> (+2.54%)	⬆️
stable-codecov	75.28% <93.44%> (-1.94%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
x/ecocredit/client/marketplace/tx.go	87.65% <76.47%> (-1.32%)	⬇️
x/ecocredit/client/testsuite/tx_marketplace.go	100.00% <100.00%> (ø)
x/ecocredit/client/tx.go	82.20% <100.00%> (+0.04%)	⬆️
app/experimental_appconfig.go	95.00% <0.00%> (-2.15%)	⬇️
x/group/testdata/tx.go	7.69% <0.00%> (ø)
x/group/server/operations.go	0.00% <0.00%> (ø)
x/group/server/msg_server.go	71.87% <0.00%> (ø)
x/group/server/query_server.go	80.26% <0.00%> (ø)
x/group/msgs.go	57.30% <0.00%> (ø)
x/group/server/server.go	58.76% <0.00%> (ø)
... and 26 more

[ryanchristo]

tACK

Can you add a changelog entry and maybe a separate section for unreleased v4.0?

## [Unreleased v4.0]

### x/ecocredit

#### Added

- [#1274](https://github.com/regen-network/regen-ledger/pull/1274) Add `cancel-sell-order` command

[technicallyty]

👍🏻