Fix errors

Author: ipavlidakis

Sources/StreamVideoSwiftUI/CallViewModel.swift

@@ -716,7 +716,7 @@ open class CallViewModel: ObservableObject {
                 Task { @MainActor [weak self] in
                     guard let self = self else { return }
                     log.debug("Detected ringing timeout, hanging up...")
-                    handleCallHangUp(ringTimeout: true)
+                    self.handleCallHangUp(ringTimeout: true)
                 }
             }
         )

Sources/StreamVideoSwiftUI/CallingViews/iOS13/BackportStateObject.swift

@@ -7,6 +7,7 @@ import SwiftUI
 
 /// A property wrapper type that instantiates an observable object.
 @propertyWrapper @available(iOS, introduced: 13, obsoleted: 14)
+@MainActor
 public final class BackportStateObject<ObjectType: ObservableObject & Sendable>: DynamicProperty, @unchecked Sendable
     where ObjectType.ObjectWillChangePublisher == ObservableObjectPublisher {