chore: add support for withenv for traksformer resource

testhelper/docker/resource/transformer/transformer.go

@@ -95,6 +95,18 @@ func WithDockerNetwork(network *docker.Network) func(*config) {
 	}
 }
 
+func WithEnv(env string) func(*config) {
+	return func(conf *config) {
+		conf.envs = append(conf.envs, env)
+	}
+}
+
+func WithRepository(repository string) func(*config) {
+	return func(conf *config) {
+		conf.repository = repository
+	}
+}
+
 func Setup(pool *dockertest.Pool, d resource.Cleaner, opts ...func(conf *config)) (*Resource, error) {
 	// Set Rudder Transformer
 	// pulls an image first to make sure we don't have an old cached version locally,