fix: spantypes in ddtrace1.0 (#3192)

fixes flake8 error introduced by a merge conflict
## Checklist
- [ ] Added to the correct milestone.
- [ ] Tests provided or description of manual testing performed is included in the code or PR.
- [ ] Library documentation is updated.
- [ ] [Corp site](https://github.com/DataDog/documentation/) documentation is updated (link to the PR).

ddtrace/filters.py

@@ -80,4 +80,4 @@ def process_trace(self, trace):
  return trace
 
  local_root = trace[0]._local_root
- return trace if local_root and local_root.span_type == SpanTypes.TEST.value else None
+ return trace if local_root and local_root.span_type == SpanTypes.TEST else None