blueprint: sshkey to users in images blueprint conversion

The sshkey customization in osbuild/images has been dropped.  In
osbuild-composer we maintain it for backwards compatibility, converting
each to a user customization, which is a superset of the sshkey.

internal/blueprint/blueprint.go

@@ -292,14 +292,7 @@ func Convert(bp Blueprint) iblueprint.Blueprint {
 			ikernel := iblueprint.KernelCustomization(*kernel)
 			customizations.Kernel = &ikernel
 		}
-		if sshkeys := c.SSHKey; sshkeys != nil {
-			isshkeys := make([]iblueprint.SSHKeyCustomization, len(sshkeys))
-			for idx := range sshkeys {
-				isshkeys[idx] = iblueprint.SSHKeyCustomization(sshkeys[idx])
-			}
-			customizations.SSHKey = isshkeys
-		}
-		if users := c.User; users != nil {
+		if users := c.GetUsers(); users != nil { // contains both user customizations and converted sshkey customizations
 			iusers := make([]iblueprint.UserCustomization, len(users))
 			for idx := range users {
 				iusers[idx] = iblueprint.UserCustomization(users[idx])

internal/blueprint/blueprint_convert_test.go

@@ -236,13 +236,11 @@ func TestConvert(t *testing.T) {
 						Name:   "kernel-name",
 						Append: "kernel-append",
 					},
-					SSHKey: []iblueprint.SSHKeyCustomization{
-						{
-							User: "ssh-user",
-							Key:  "ssh-key",
-						},
-					},
 					User: []iblueprint.UserCustomization{
+						{
+							Name: "ssh-user", // converted from sshkey
+							Key:  common.ToPtr("ssh-key"),
+						},
 						{
 							Name:        "user-name",
 							Description: common.ToPtr("user-desc"),