imp: added length validation to MsgCreateClient and CounterpartyMerklePrefix.

[yihuang]

Description

closes: #8775

---

Before we can merge this PR, please make sure that all the following items have been
checked off. If any of the checklist items are not applicable, please leave them but
write a little note why.

• Linked to GitHub issue with discussion and accepted design, OR link to spec that describes this work.
• Include changelog entry when appropriate (e.g. chores should be omitted from changelog).
• Wrote unit and integration tests if relevant.
• Updated documentation (docs/) if anything is changed.
• Added godoc comments if relevant.
• Self-reviewed Files changed in the GitHub PR explorer.
• Provide a conventional commit message to follow the repository standards.

[codecov]

Codecov Report

❌ Patch coverage is 85.71429% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 66.61%. Comparing base (dfbe362) to head (bb1b60b).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...les/light-clients/07-tendermint/consensus_state.go	33.33%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #8774      +/-   ##
==========================================
+ Coverage   66.58%   66.61%   +0.02%     
==========================================
  Files         326      326              
  Lines       17114    17128      +14     
==========================================
+ Hits        11396    11410      +14     
  Misses       5023     5023              
  Partials      695      695              

Flag	Coverage Δ
08-wasm	64.81% <ø> (ø)
ibc-go	66.67% <85.71%> (+0.02%)	⬆️

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