refactor: move container generation to distro modules

distro/ubuntu/ubuntu_test.go

@@ -0,0 +1,22 @@
+package ubuntu
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"code.dumpstack.io/tools/out-of-tree/distro"
+)
+
+func TestUbuntu(t *testing.T) {
+	assert := assert.New(t)
+
+	u := Ubuntu{release: "22.04", container: "out_of_tree_ubuntu_22__04"}
+
+	assert.Equal(u.ID(), distro.Ubuntu)
+	assert.Equal(u.Release(), "22.04")
+
+	assert.True(u.Equal(distro.Distro{Release: "22.04", ID: distro.Ubuntu}))
+
+	assert.NotEmpty(u.Packages())
+}