People and employers will judge you regardless. They will judge you because of your religion, your physical illness, your skin color, race, gender, sex, weight, tattoos (unrelated to this issue), etc. They're not (and should not) be allowed of course. And I'm sure they won't say it to your face either.

But given everything else, I would be real surprised if everything else being equal, a small semicolon becomes the reason someone is fired or does not get a job. If the particular job requires certain level of mental stability or freedom from any mental health issues, I'm sure they have other ways to check into this and find out, than to rely on a tattoo which symbolizes personal past of self harm or support for those who are dealing with this issue or have lost someone to this.