docs: Fix usage to reflect latest refactor

Author: keelerm84

README.md

@@ -39,13 +39,11 @@ $ pip install launchdarkly-openfeature-server
 ### Usage
 
 ```python
-from ldclient import Config, LDClient
+from ldclient import Config
 from ld_openfeature import LaunchDarklyProvider
-from openfeature.evaluation_context import EvaluationContext
 from openfeature import api
 
-ld_client = LDClient(config=Config("sdk-key"))
-openfeature_provider = LaunchDarklyProvider(ld_client)
+openfeature_provider = LaunchDarklyProvider(Config("sdk-key"))
 
 api.set_provider(openfeature_provider)