`rescueLostKitty` can be replaced with a check

[Arachnid]

Description

rescueLostKitty exists to restore ownership of kitties accidentally transferred to the token contract itself. This can be replaced by a simple check on transfer that prevents this happening in the first place.

Scenario

1. User transfers a kitty to the token contract
2. rescueLostKitty is called.

Impact

Some inconvenience for the user and for the maintainers of the contract.

Reproduction

See Scenario.

Fix

Add a check require(to != address(this)) in the transfer function.

[dete]

Thanks, @Arachnid! (I may be embarrassed, but I'm still grateful!)

[kimcope]

Thanks for your participation, @Arachnid! Our team has reviewed your submission, and we are pleased to reward you for your report.

Impact: Low
Likelihood: Low
Points: 50

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