Log lutron_caseta exception on pairing failure (#140776)

homeassistant/components/lutron_caseta/config_flow.py

@@ -123,7 +123,8 @@ class LutronCasetaFlowHandler(ConfigFlow, domain=DOMAIN):
             assets = None
             try:
                 assets = await async_pair(self.data[CONF_HOST])
-            except (TimeoutError, OSError):
+            except (TimeoutError, OSError) as exc:
+                _LOGGER.debug("Pairing failed", exc_info=exc)
                 errors["base"] = "cannot_connect"
 
             if not errors: