fix null negative_prompt on get requests

Small typo that causes a bug when returning negative prompts from the get request.

Author: Hugo-Matias

modules/api/api.py

@@ -305,7 +305,7 @@ def get_promp_styles(self):
         styleList = []
         for k in shared.prompt_styles.styles:
             style = shared.prompt_styles.styles[k]
-            styleList.append({"name":style[0], "prompt": style[1], "negative_prompr": style[2]})
+            styleList.append({"name":style[0], "prompt": style[1], "negative_prompt": style[2]})
 
         return styleList