test: add integration test for the rollback cmd

[yihuang]

Description

• check the rollback cmd works in integration tests

depends: cosmos/cosmos-sdk#13089

---

For contributor use:

• Targeted PR against correct branch (see CONTRIBUTING.md)
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
• Code follows the module structure standards.
• Wrote unit and integration tests
• Updated relevant documentation (docs/) or specification (x/<module>/spec/)
• Added relevant godoc comments.
• Added a relevant changelog entry to the Unreleased section in CHANGELOG.md
• Re-reviewed Files changed in the Github PR explorer

---

For admin use:

• Added appropriate labels to PR (ex. WIP, R4R, docs, etc)
• Reviewers assigned
• Squashed all commits, uses message "Merge pull request #XYZ: [title]" (coding standards)

[facs95]

LGTM! Awesome test.. can you please add a changelog?

[yihuang]

LGTM! Awesome test.. can you please add a changelog?

Oh, I forgot to do that, thanks for the help 👍