Allow custom images on iterative_cml_runner resource (#266)

Author: 0x2b3bfa0

iterative/resource_runner.go

@@ -89,7 +89,9 @@ func resourceRunner() *schema.Resource {
 			},
 			"image": &schema.Schema{
 				Type:     schema.TypeString,
-				Computed: true,
+				ForceNew: true,
+				Optional: true,
+				Default:  "",
 			},
 			"spot": &schema.Schema{
 				Type:     schema.TypeBool,