WarpCore shouldn't allow for recipients to be the remote router or remote collateral token

[tkporter]

Problem

Sadly recently someone used the UI to do a Stride -> Eclipse transfer, and they set the recipient as the mint address on the Eclipse side

Solution

In validateTransfer, we should require the recipient is not the destination router or token address

Nice to Have

Describe non-essential extensions to the solution
Additional features which should be implemented if they are easy to accommodate but otherwise can be skipped

[0x471]

Hi ,I’ve added a check to ensure the recipient is not the destination token address in the validateTransfer function. You can see the changes here:
main...0x471:hyperlane-monorepo:warp/validateTransfer-recipientConflict.

I wasn't able to find how to access the destination router object to fetch the address. Any guidance on this would be appreciated.

Happy to submit a PR once it's done, thanks!

@jmrossy @tkporter