Use UnpackAny for ExtensionOptionsWeb3Tx

[trinitys7]

Description

---

Closes #761

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.

PR review checkboxes:

I have...

• Added a relevant changelog entry to the Unreleased section in CHANGELOG.md
• Targeted PR against the correct branch
• included the correct type prefix in the PR title
• Linked to the GitHub issue with discussion and accepted design
• Targets only one GitHub issue
• Wrote unit and integration tests
• Wrote relevant migration scripts if necessary
• All CI checks have passed
• Added relevant godoc comments
• Updated the scripts for local run, e.g genesis_config_commands.sh if the PR changes parameters
• Add an issue in the e2e-tests repo if necessary

SDK Checklist

• Import/Export Genesis
• Registered Invariants
• Registered Events
• Updated openapi.yaml
• No usage of go map
• No usage of time.Now()
• Used fixed point arithmetic and not float arithmetic
• Avoid panicking in Begin/End block as much as possible
• No unexpected math Overflow
• Used sendCoin and not SendCoins
• Out-of-block compute is bounded
• No serialized ID at the end of store keys
• UInt to byte conversion should use BigEndian

Full security checklist here

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For Reviewer:

• Confirmed the correct type prefix in the PR title
• Reviewers assigned
• Confirmed all author checklist items have been addressed

---;

After reviewer approval:

• In case the PR targets the main branch, PR should not be squash merge in order to keep meaningful git history.
• In case the PR targets a release branch, PR must be rebased.

[codecov]

Codecov Report

Attention: Patch coverage is 50.00000% with 2 lines in your changes are missing coverage. Please review.

Project coverage is 31.84%. Comparing base (0ccb065) to head (c4ff1e1).
Report is 2 commits behind head on main.

Files	Patch %	Lines
app/ante/eip712.go	50.00%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #777      +/-   ##
==========================================
+ Coverage   31.50%   31.84%   +0.34%     
==========================================
  Files         233      233              
  Lines       32641    32641              
==========================================
+ Hits        10282    10393     +111     
+ Misses      20740    20601     -139     
- Partials     1619     1647      +28     

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[mtsitrin]

waiting for audit team