[openweathermap] minor documentation typo (openhab#7829)

Signed-off-by: Holger Eisold holgereisold@gmx.de
Signed-off-by: Daan Meijer <daan@studioseptember.nl>

bundles/org.openhab.binding.openweathermap/README.md

@@ -58,7 +58,7 @@ Once the system location will be changed, the background discovery updates the c
 
 Once the parameters `forecastHours` or `forecastDays` will be changed, the available channel groups on the thing will be created or removed accordingly.
 
-### Current UV INdex And Forecast
+### Current UV Index And Forecast
 
 | Parameter | Description |
 |----------------|--------------------------------------------------------------------------------------------------------------------------------|