fix: handle error without line and column in loc

[fi3ework]

Description

fix #12293

Additional context

Delete err.loc when all the fields in it are nullish to prevent undefined in trace such like /Users/fi3ework/OSS/vite-repro/i12293/src/components/HelloWorld.vue?vue&type=style&index=0&scoped=e17ea971&lang.css:undefined:undefined.

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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[benmccann]

Thanks for this! Do you think there's any test we can add?

[fi3ework]

Thanks for this! Do you think there's any test we can add?

Sure, but the logic here is a bit messy. I would like to add some basic tests later. Feel free to merge this first if the bug should be fixed soon.

see #12312 (comment)