Preserve project file encoding on update

Keep the original project file encoding when rewriting updated NuGet package versions. This avoids forcing the default encoding during XML writes and stores the XML output before truncating the file stream.

framework/src/Volo.Abp.Cli.Core/Volo/Abp/Cli/ProjectModification/VoloNugetPackagesVersionUpdater.cs

@@ -449,12 +449,14 @@ public class VoloNugetPackagesVersionUpdater : ITransientDependency
                         }
                     }
 
+                    var updatedXml = doc.OuterXml;
+
                     fs.Seek(0, SeekOrigin.Begin);
                     fs.SetLength(0);
 
-                    using (var sw = new StreamWriter(fs, DefaultEncoding))
+                    using (var sw = new StreamWriter(fs, sr.CurrentEncoding))
                     {
-                        await sw.WriteAsync(doc.OuterXml);
+                        await sw.WriteAsync(updatedXml);
                         await sw.FlushAsync();
                     }
                 }