[BUG] Builtin tests and filters don't get a special scope.

[ROpdebee]

Summary

The built-in filters, tests, and globals should probably be scoped as support.

Expected Behaviour

   {{ poetry_bin_path | default('/usr/local/bin/poetry') }}
##                      ^^^^^^^ support.function.jinja

Actual Behaviour

   {{ poetry_bin_path | default('/usr/local/bin/poetry') }}
##                      ^^^^^^^ variable.function.jinja

How to Reproduce

See above.

Problematic Jinja2 template.

{{ poetry_bin_path | default('/usr/local/bin/poetry') }}

Environment

Same as earlier.

Additional context

Scoping the built-ins as support. will also lead to more varied highlighting on some color schemes, which IMO looks better.

Used in screenshots: Theme - Spacegray, Base16 Ocean color scheme from Base16, Source Code Pro as font.