Update bulgaria code

Author: trailhead-loris

index.html

@@ -32,7 +32,7 @@ <h1>Test Agentforce</h1>
             <option value="en_US">English (US)</option>
             <option value="es">Español (ES)</option>
             <option value="fr">Français (FR)</option>
-            <option value="bg">Bulgarian (BG) </option>
+            <option value="bg_BG">Bulgarian (BG) </option>
         </select>
     </div>
 
@@ -144,3 +144,4 @@ <h1>Test Agentforce</h1>
 
 
 
+