chore: release v4.0.1

[RiccardoM]

Description

This PR implements the changes made into v4.0.1 to fix the v4.0.0 upgrade handler

---

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...

• 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

All items are required. Please add a note if the item is not applicable and please add
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)

[codecov]

Codecov Report

Merging #952 (ba2540f) into master (8adb7c9) will decrease coverage by 0.15%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #952      +/-   ##
==========================================
- Coverage   82.76%   82.60%   -0.16%     
==========================================
  Files         166      167       +1     
  Lines       14014    14132     +118     
==========================================
+ Hits        11598    11674      +76     
- Misses       1943     1979      +36     
- Partials      473      479       +6     

Impacted Files	Coverage Δ
x/posts/types/models.go	75.75% <0.00%> (-1.73%)	⬇️
x/posts/module.go	8.00% <0.00%> (-0.34%)	⬇️
x/posts/legacy/v3/store.go	69.15% <0.00%> (ø)
x/reactions/keeper/msg_server.go	96.40% <0.00%> (+0.01%)	⬆️
x/posts/keeper/msg_server.go	89.76% <0.00%> (+0.03%)	⬆️
x/posts/types/msgs.go	96.96% <0.00%> (+0.13%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 8adb7c9...ba2540f. Read the comment docs.