remove threat status text if no iucn data is available

lib/plantnet/parser.ex

@@ -79,13 +79,15 @@ defmodule PlantIdDiscordBot.PlantNet.Parser do
     best_result = hd(data["results"])
     other_results = tl(data["results"])
     best_guess_name = best_result["species"]["scientificNameWithoutAuthor"]
+    best_result_iucn_category = best_result["iucn"]["category"]
     score = round(best_result["score"] * 100) |> Integer.to_string()
 
     """
     My best guess is **#{best_guess_name}** with a confidence of **#{score}%**. Common names include **#{Enum.join(best_result["species"]["commonNames"], ", ")}**.
 
     [GBIF](<#{best_result["gbif_url"]}>) | [PFAF](<#{best_result["pfaf_url"]}>) | [POWO](<#{best_result["powo_url"]}>)
-    Threat status: #{best_result["iucn"]["category"]}
+
+    #{if best_result_iucn_category, do: "Threat status: #{best_result_iucn_category}", else: ""}
 
     #{get_alternatives(other_results)}
     """