fix: remove ResultCollector import from composition branch __init__.py

ResultCollector belongs to feat/result-export, not this branch.
Its import caused a ty unresolved-import error in CI.

Author: zurfjereluhmie

src/evalwire/__init__.py

@@ -18,7 +18,6 @@
     make_weighted_evaluator,
 )
 from evalwire.observability import setup_observability
-from evalwire.results import ResultCollector
 from evalwire.runner import ExperimentRunner
 from evalwire.uploader import DatasetUploader
 
@@ -29,7 +28,6 @@
 __all__ = [
     "DatasetUploader",
     "ExperimentRunner",
-    "ResultCollector",
     "make_all_pass_evaluator",
     "make_any_pass_evaluator",
     "make_contains_evaluator",