Address review comments

Signed-off-by: Pablo Chacin <pablochacin@gmail.com>

modules/k6/k6.go

@@ -9,8 +9,6 @@ import (
 	"github.com/docker/docker/api/types/mount"
 
 	"github.com/testcontainers/testcontainers-go"
-	"github.com/testcontainers/testcontainers-go/internal/testcontainersdocker"
-	"github.com/testcontainers/testcontainers-go/internal/testcontainerssession"
 	"github.com/testcontainers/testcontainers-go/wait"
 )
 
@@ -55,18 +53,18 @@ func SetEnvVar(variable string, value string) testcontainers.CustomizeRequestOpt
 }
 
 // WithCache sets a volume as a cache for building the k6 binary
-// If a volume name is provided in the TC_K6_BUILD_CACHE, this volume is used.
-// If no value is provided, a volume is created and removed when the test session ends.
+// If a volume name is provided in the TC_K6_BUILD_CACHE, this volume is used and it will
+// persist across test sessions.
+// If no value is provided, a volume is created and automatically deleted when the test session ends.
 func WithCache() testcontainers.CustomizeRequestOption {
 	var volOptions *mount.VolumeOptions
 
 	cacheVol := os.Getenv("TC_K6_BUILD_CACHE")
 	// if no volume is provided, create one and ensure add labels for garbage collection
 	if cacheVol == "" {
-		sessionID := testcontainerssession.SessionID()
-		cacheVol = fmt.Sprintf("k6-cache-%s", sessionID)
+		cacheVol = fmt.Sprintf("k6-cache-%s", testcontainers.SessionID())
 		volOptions = &mount.VolumeOptions{
-			Labels: testcontainersdocker.DefaultLabels(sessionID),
+			Labels: testcontainers.GenericLabels(),
 		}
 	}