Enhance debug logging in FolioAuth and improve error message in prepare_payload function

Author: bltravis

src/folioclient/FolioClient.py

@@ -2452,4 +2452,4 @@ def prepare_payload(payload: Dict | str) -> bytes:
     elif isinstance(payload, str):
         return payload.encode("utf-8")
     else:
-        raise TypeError("Payload must be a dictionary or a string.")
+        raise TypeError(f"Payload must be a dictionary or a string, got {type(payload).__name__}")

src/folioclient/_httpx.py

@@ -69,7 +69,7 @@ def tenant_id(self) -> str:
     @tenant_id.setter
     def tenant_id(self, value: str):
         if value != self._tenant_id:
-            logger.debug("Setting tenant_id to %s", value)
+            logger.debug("Switching tenant_id from %s to %s", self._tenant_id, value)
             self._tenant_id = value
 
     def reset_tenant_id(self):