osbuild2: selinux stage - introduce force_autorelabel option

This was added in osbuild: https://github.com/osbuild/osbuild/pull/875

Introduce the same option in composer and make it optional by specifying
it as a pointer to bool value. It would work the same even if it was
there every time, but as it should be an edge case, don't use it
everywhere. Also osbuild doesn't require it to be present, so it seems
like the right thing to do.

internal/osbuild2/selinux_stage.go

@@ -5,8 +5,9 @@ package osbuild2
 // A file contexts configuration file is sepcified that describes
 // the filesystem labels to apply to the image.
 type SELinuxStageOptions struct {
-	FileContexts string            `json:"file_contexts"`
-	Labels       map[string]string `json:"labels,omitempty"`
+	FileContexts     string            `json:"file_contexts"`
+	Labels           map[string]string `json:"labels,omitempty"`
+	ForceAutorelabel *bool             `json:"force_autorelabel,omitempty"`
 }
 
 func (SELinuxStageOptions) isStageOptions() {}

internal/osbuild2/stage_test.go

@@ -452,6 +452,18 @@ func TestStage_UnmarshalJSON(t *testing.T) {
 				data: []byte(`{"type":"org.osbuild.selinux","options":{"file_contexts":""}}`),
 			},
 		},
+		{
+			name: "selinux-force_autorelabel",
+			fields: fields{
+				Type: "org.osbuild.selinux",
+				Options: &SELinuxStageOptions{
+					ForceAutorelabel: common.BoolToPtr(true),
+				},
+			},
+			args: args{
+				data: []byte(`{"type":"org.osbuild.selinux","options":{"file_contexts":"","force_autorelabel":true}}`),
+			},
+		},
 		{
 			name: "selinux.config-empty",
 			fields: fields{