Automation takes this and a whole class of problems out of the interpersonal domain. Failed tests make the build fail. Who ever breaks the build buy donuts for the team. Easy, solved and no personal issues. Include a linter in the build, incorrect formatting fails the build. The team decided on the standard format (tabs vs spaces, 4/2 spaces, brace same line or next line etc). More donuts. No arguments because linting rules were decided by the team. New members adapt.
