[ecobee] fix NullPointerException in EcobeeAccountBridgeHandler.refreshThermostats() (openhab#16442)

Signed-off-by: Rob Nielsen <[email protected]>

Author: robnielsen

bundles/org.openhab.binding.ecobee/src/main/java/org/openhab/binding/ecobee/internal/handler/EcobeeAccountBridgeHandler.java

@@ -220,10 +220,13 @@ private void refreshThermostats() {
             refreshThermostatsCounter.set(refreshIntervalNormal);
             SummaryResponseDTO summary = api.performThermostatSummaryQuery();
             if (summary != null && summary.hasChanged(previousSummary) && !thermostatIds.isEmpty()) {
-                for (ThermostatDTO thermostat : api.performThermostatQuery(thermostatIds)) {
-                    EcobeeThermostatBridgeHandler handler = thermostatHandlers.get(thermostat.identifier);
-                    if (handler != null) {
-                        handler.updateChannels(thermostat);
+                List<ThermostatDTO> thermostats = api.performThermostatQuery(thermostatIds);
+                if (thermostats != null) {
+                    for (ThermostatDTO thermostat : thermostats) {
+                        EcobeeThermostatBridgeHandler handler = thermostatHandlers.get(thermostat.identifier);
+                        if (handler != null) {
+                            handler.updateChannels(thermostat);
+                        }
                     }
                 }
             }