Add null-safety for list props with type dynamic

lib/features/composer/domain/state/download_image_as_base64_state.dart

@@ -29,5 +29,5 @@ class DownloadImageAsBase64Failure extends FeatureFailure {
   DownloadImageAsBase64Failure(this.exception);
 
   @override
-  List<Object> get props => [exception];
+  List<Object?> get props => [exception];
 }

lib/features/composer/domain/state/get_autocomplete_state.dart

@@ -17,5 +17,5 @@ class GetAutoCompleteFailure extends FeatureFailure {
   GetAutoCompleteFailure(this.exception);
 
   @override
-  List<Object> get props => [exception];
+  List<Object?> get props => [exception];
 }

lib/features/composer/domain/state/get_device_contact_suggestions_state.dart

@@ -17,5 +17,5 @@ class GetDeviceContactSuggestionsFailure extends FeatureFailure {
   GetDeviceContactSuggestionsFailure(this.exception);
 
   @override
-  List<Object> get props => [exception];
+  List<Object?> get props => [exception];
 }

lib/features/composer/domain/state/save_email_address_state.dart

@@ -14,5 +14,5 @@ class SaveEmailAddressFailure extends FeatureFailure {
   SaveEmailAddressFailure(this.exception);
 
   @override
-  List<Object> get props => [exception];
+  List<Object?> get props => [exception];
 }

lib/features/composer/domain/state/save_email_as_drafts_state.dart

@@ -33,5 +33,5 @@ class SaveEmailAsDraftsFailure extends FeatureFailure {
   SaveEmailAsDraftsFailure(this.exception);
 
   @override
-  List<Object> get props => [exception];
+  List<Object?> get props => [exception];
 }

lib/features/composer/domain/state/update_email_drafts_state.dart

@@ -33,5 +33,5 @@ class UpdateEmailDraftsFailure extends FeatureFailure {
   UpdateEmailDraftsFailure(this.exception);
 
   @override
-  List<Object> get props => [exception];
+  List<Object?> get props => [exception];
 }