Base branch is #24138

Description

Upon testing the new @spruceid/siwe-parser changes, @digiwand noticed that message parsing would fail when using the MetaMask Test dApp. During this investigation, it was identified that the parsing failed due to the isEIP55Address check.

This is due to the fact that an EIP-55 address is case sensitive, but MetaMask lowercases the wallet address before returning it to an eth_accounts call. This means that when dApps attempt to request a SIWE message (using this lowecase address), the operation would fail to parse.

This change removes that check, and provides the consistent experience we have already been giving prior to the @spruceid/siwe-parser v2 upgrade.

Related issues

Adds to #24138

Pre-merge author checklist

• I’ve followed MetaMask Coding Standards.
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Pre-merge reviewer checklist

• I've manually tested the PR (e.g. pull and build branch, run the app, test code being changed).
• I confirm that this PR addresses all acceptance criteria described in the ticket it closes and includes the necessary testing evidence such as recordings and or screenshots.