Upgrade handler

[vuong177]

Description

• Upgrade handler for SDK 46.

Closes: #XXXX

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Author Checklist

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please add links to any relevant follow up issues.

I have...

• included the correct type prefix in the PR title
• added ! to the type prefix if API or client breaking change
• targeted the correct branch (see PR Targeting)
• provided a link to the relevant issue or specification
• followed the guidelines for building modules
• included the necessary unit and integration tests
• added a changelog entry to CHANGELOG.md
• included comments for documenting Go code
• 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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your handle next to the items reviewed if you only reviewed selected items.

I have...

• confirmed the correct type prefix in the PR title
• confirmed ! in the type prefix if API or client breaking change
• confirmed all author checklist items have been addressed
• reviewed state machine logic
• reviewed API design and naming
• reviewed documentation is accurate
• reviewed tests and test coverage
• manually tested (if applicable)

[faddat]

Hey guys, pls don't forget to set the store key for the ephocs module to nil -- iirc that's the right way to remove a module. I think. You may wanna double check on that.

Thanks!

[faddat]

As you work on this, recommend that you reference and contribute to this document:

• docs: improve UPGRADING.md instructions for v0.46.0 cosmos/cosmos-sdk#12646

[faddat]

Also check out the release nodes please:

https://github.com/cosmos/cosmos-sdk/releases/tag/v0.46.0

[faddat]

STYLE POINTS, FOR UPGRADE.SH

good work Hieu

[mustafapylons]

few typos, otherwise code is good.

[mustafapylons]

Looks good to me now.