fix missing return values on platform channels for destroyTexture

android/src/main/kotlin/app/polyvox/filament/PolyvoxFilamentPlugin.kt

@@ -201,6 +201,7 @@ class PolyvoxFilamentPlugin: FlutterPlugin, MethodCallHandler, ActivityAware, Lo
           _surfaceTextureEntry!!.release();
           _surface = null
           _surfaceTextureEntry = null
+          result.success(true)
         }
         "resize" -> {
             val args = call.arguments as List<Any>

ios/Classes/SwiftPolyvoxFilamentPlugin.swift

@@ -187,6 +187,7 @@ public class SwiftPolyvoxFilamentPlugin: NSObject, FlutterPlugin, FlutterTexture
                 }
                 self.flutterTextureId = nil 
                 self.pixelBuffer = nil
+                result(true)
             case "resize":
                 let args = call.arguments as! [Any]
                 let width = UInt32(args[0] as! Int64)

macos/Classes/SwiftPolyvoxFilamentPlugin.swift

@@ -162,6 +162,7 @@ public class SwiftPolyvoxFilamentPlugin: NSObject, FlutterPlugin, FlutterTexture
             self.flutterTextureId = nil 
             self.pixelBuffer = nil
             self.metalTexture = nil
+            result(true)
         case "resize":
             let args = call.arguments as! [Any]
             let width = UInt32(args[0] as! Int64)