Revert "fix: disable Client Side Stats by default (#756)"

This reverts commit 52bcf21.

Author: ojproductions

datadog_lambda/config.py

@@ -146,13 +146,6 @@ def _reset(self):
 if "DD_REMOTE_CONFIGURATION_ENABLED" not in os.environ:
     os.environ["DD_REMOTE_CONFIGURATION_ENABLED"] = "false"
 
-# disable css to prevent double counting in lambda
-os.environ["DD_TRACE_STATS_COMPUTATION_ENABLED"] = "false"
-
-# unset css aliases to ensure it is disabled
-if "DD_TRACE_COMPUTE_STATS" in os.environ:
-    del os.environ["DD_TRACE_COMPUTE_STATS"]
-
 if (
     "DD_INSTRUMENTATION_TELEMETRY_ENABLED" not in os.environ
     and not config.sca_enabled