Fix test for temp_units

Solves #1834

esphome/nspanel_esphome_core.yaml

@@ -1867,7 +1867,7 @@ script:
       - lambda: |-
           float unit_based_temperature = id(temp_nspanel).state;
           char buffer[15]; // Buffer for formatted temperature string
-          if ("${temp_units}"[0] == 'F' || "${temp_units}"[0] == 'f') {
+          if ("${temp_units}"[0] == 'F' || "${temp_units}"[0] == 'f' || "${temp_units}"[1] == 'F' || "${temp_units}"[1] == 'f') {
               unit_based_temperature = (unit_based_temperature * 9.0 / 5.0) + 32; // Convert to Fahrenheit if necessary
               snprintf(buffer, sizeof(buffer), "%.0f°F", unit_based_temperature); // Fahrenheit with no decimal
           } else {