Add docker.#Set for updating image metadata

Signed-off-by: Helder Correia <174525+helderco@users.noreply.github.com>

pkg/universe.dagger.io/docker/test/docker.bats

@@ -22,3 +22,7 @@ setup() {
     dagger up ./run-export-directory-test.cue
     dagger up ./image-config-test.cue
 }
+
+@test "docker.#Set" {
+    dagger up ./set.cue
+}