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Environment

macOS
Installed with Homebrew
Vale 3.9.5

Describe the bug / provide steps to reproduce it

I've tested --filter expressions like the docs show and it seems Vale only now supports filters saved in files.

vale --filter='"heading" in .Scope' awk.md
filter '"heading" in .Scope' not found

I think this refactor is what caused the issue:

df48b17#diff-f491ac2d9f7dcb3cb5657a04e5fe526d6702596c62c3bec542816356f7c44229L23

And the unit tests for Vale only seem to cover using saved filters, not CLI expressions.