[test] Codex tests (#3911)

lnbits/core/models/tinyurl.py

@@ -1,4 +1,6 @@
-from pydantic import BaseModel
+from datetime import datetime, timezone
+
+from pydantic import BaseModel, Field
 
 
 class TinyURL(BaseModel):
@@ -6,4 +8,4 @@ class TinyURL(BaseModel):
     url: str
     endless: bool
     wallet: str
-    time: float
+    time: datetime = Field(default_factory=lambda: datetime.now(timezone.utc))