fix: handle null values when converting arrays to set and list

Author: OnestarLee

android/src/main/java/com/sendbird/calls/reactnative/utils/CallsUtils.kt

@@ -277,15 +277,15 @@ object CallsUtils {
     fun convertArrayToSet(array: ReadableArray): Set<String> {
         val set = mutableSetOf<String>()
         for (i in 0 until array.size()) {
-            set.add(array.getString(i))
+            array.getString(i)?.let { set.add(it) }
         }
         return set
     }
 
     fun convertArrayToList(array: ReadableArray): List<String> {
         val list = mutableListOf<String>()
         for (i in 0 until array.size()) {
-            list.add(array.getString(i))
+            array.getString(i)?.let { list.add(it) }
         }
         return list
     }

android/src/oldarch/java/com/sendbird/calls/reactnative/RNSendbirdCallsModule.kt

@@ -57,8 +57,8 @@ class RNSendbirdCallsModule(private val reactContext: ReactApplicationContext) :
     override fun getOngoingCalls(promise: Promise) = module.getOngoingCalls(promise)
     @ReactMethod
     override fun getDirectCall(callId: String, promise: Promise) = module.getDirectCall(callId, promise)
-    @ReactMethod
-    override fun initialize(appId: String) = module.initialize(appId)
+    @ReactMethod(isBlockingSynchronousMethod = true)
+    override fun initialize(appId: String): Boolean = module.initialize(appId)
     @ReactMethod
     override fun authenticate(authParams: ReadableMap, promise: Promise) = module.authenticate(authParams, promise)
     @ReactMethod