Word Swap Qwerty Failure Bug Fix

[jstzwj]

Summary

This PR fixes an IndexError in WordSwapQWERTY when random_one is True and the word contains non-qwerty characters.

This PR is related to #717

Changes

• Check if the adjacent_char list is empty before calling random.choice

Checklist

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[jxmorris12]

thanks :) this is better!