Remove unnecessary holdout test files

- Remove holdout_test.go since holdout logic is in config.go per TDD
- Remove TestMapFeaturesWithHoldoutIds test since HoldoutIds don't exist
- Follows reviewer requirement: no holdout ID exposure, holdouts in config.go

Author: Mat001

pkg/config/datafileprojectconfig/mappers/feature_test.go

@@ -78,33 +78,3 @@ func TestMapFeatures(t *testing.T) {
 	assert.Equal(t, expectedExperimentMap, experimentMap)
 }
 
-func TestMapFeaturesWithHoldoutIds(t *testing.T) {
-	const testFeatureFlagString = `{
-		"id": "22222",
-		"key": "test_feature_22222",
-		"rolloutId": "42222",
-		"experimentIds": ["32222"],
-		"variables": [{"defaultValue":"test","id":"2","key":"var","type":"string"}]
-	}`
-
-	var rawFeatureFlag datafileEntities.FeatureFlag
-	var json = jsoniter.ConfigCompatibleWithStandardLibrary
-	json.Unmarshal([]byte(testFeatureFlagString), &rawFeatureFlag)
-
-	rawFeatureFlags := []datafileEntities.FeatureFlag{rawFeatureFlag}
-	rollout := entities.Rollout{ID: "42222"}
-	rolloutMap := map[string]entities.Rollout{
-		"42222": rollout,
-	}
-	experiment32222 := entities.Experiment{ID: "32222"}
-	experimentMap := map[string]entities.Experiment{
-		"32222": experiment32222,
-	}
-	featureMap := MapFeatures(rawFeatureFlags, rolloutMap, experimentMap)
-
-	// Verify that the feature is created properly
-	feature := featureMap["test_feature_22222"]
-
-	assert.Equal(t, "22222", feature.ID)
-	assert.Equal(t, "test_feature_22222", feature.Key)
-}