fix build

Pilz.Updating.Client/Pilz.Updating.Client.csproj

@@ -4,6 +4,7 @@
     <TargetFrameworks>net8.0;netstandard2.0</TargetFrameworks>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
+    <LangVersion>latest</LangVersion>
   </PropertyGroup>
   
   <PropertyGroup>

Pilz.Updating.Client/UpdateClientEventArgs.cs

@@ -2,5 +2,5 @@
 
 public class UpdateClientEventArgs(UpdateClient client) : EventArgs
 {
-    public UpdateClient Client { get; init; } = client;
+    public UpdateClient Client { get; } = client;
 }

Pilz.Updating.Client/Utils.cs

@@ -40,7 +40,9 @@ public static class Utils
                 if (triesLeft == 0 && File.Exists(destFileName))
                 {
                     oldFile = destFileName + ".old";
-                    File.Move(destFileName, oldFile, true);
+                    if (File.Exists(oldFile))
+                        File.Delete(oldFile);
+                    File.Move(destFileName, oldFile);
                     triesLeft++;
                     Thread.Sleep(100);
                 }