[bud-eslint] .eslintignore unknown config format

I added a .eslintignore file to my theme as described in the docs, but I get a warning.

[sage] [@roots/bud-eslint] › ⚠  Unknown eslint config format. Please update `.eslintignore` to use one of: js, cjs, mjs, json, yml, yaml
[sage] [@roots/bud-eslint] › ⚠  Unknown eslint config format. Parsed as yml.

According to the eslint docs it’s just a normal text file, just like the .gitignore.

It’s not blocking for now, but I would like to fix the warning in my project.