Someone who lies to you about small stuff will usually lie about you in small ways too.

Small lies look harmless because the stakes are low, and that is precisely what makes them informative. Somebody who adjusts the facts when nothing is at risk has shown you their default setting, and a default does not switch itself off once you become the subject. The size of a lie tells you about the situation. The fact of it tells you about the person.

When a friend lies about something that did not need lying about, take it seriously as information. You do not have to confront them or cut them loose. Just carry less of what they tell you about other people.