Not sure if you're joking, but the etymology of this word does not appear to be racist. According to [0], it derives from the same root as "niggardly", which according to [1], is unrelated to the racial epithet.

[0]: https://en.wiktionary.org/wiki/niggle [1]: https://en.wiktionary.org/wiki/niggard#English

This is a great opportunity for you to learn more English language.