Previously, drift detection triggered whenever the DRIFT_DETECTION_ENABLED option was on
and a vector was generated, regardless of execution status.
This caused false positives because exception messages (abnormal values) were compared
against normal input vectors when functions failed.

This commit restricts drift detection to execute only when the execution status is 'SUCCESS',
preventing errors from being misidentified as semantic drift.

Signed-off-by: Jun Yeong Kim <junyeonggim5@gmail.com>