chore(gemini): new gemini model

Author: dqnk

lua/parrot/provider/gemini.lua

@@ -168,7 +168,7 @@ function Gemini:get_available_models(online)
     "gemini-1.5-flash-8b-exp-0827",
     "gemini-1.5-flash-8b-exp-0924",
     "gemini-2.5-pro-exp-03-25",
-    "gemini-2.5-pro-preview-03-25",
+    "gemini-2.5-pro-preview-05-06",
     "gemini-2.0-flash-exp",
     "gemini-2.0-flash",
     "gemini-2.0-flash-001",