TestBuildUserNamespaceValidateCapabilitiesAreV2: use correct image name

This currently doesn't make a difference, because load.FrozenImagesLinux()
currently loads all frozen images, not just the specified one, but in case
that is fixed/implemented at some point.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
(cherry picked from commit 26965fbfa0e68d7dee49406b21fc0b8e01994205)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

integration/build/build_userns_linux_test.go

@@ -41,7 +41,7 @@ func TestBuildUserNamespaceValidateCapabilitiesAreV2(t *testing.T) {
 	ctx := context.Background()
 	clientUserRemap := dUserRemap.NewClientT(t)
 
-	err = load.FrozenImagesLinux(clientUserRemap, "buildpack-deps:buster")
+	err = load.FrozenImagesLinux(clientUserRemap, "debian:bullseye")
 	assert.NilError(t, err)
 
 	dUserRemapRunning := true