Update nuget packages

DiscordChatExporter.Gui/DiscordChatExporter.Gui.csproj

@@ -135,13 +135,13 @@
       <Version>1.1.3</Version>
     </PackageReference>
     <PackageReference Include="MaterialDesignThemes">
-      <Version>2.5.0.1205</Version>
+      <Version>2.5.1</Version>
     </PackageReference>
     <PackageReference Include="Ookii.Dialogs.Wpf">
       <Version>1.0.0</Version>
     </PackageReference>
     <PackageReference Include="PropertyChanged.Fody">
-      <Version>2.6.0</Version>
+      <Version>2.6.1</Version>
     </PackageReference>
     <PackageReference Include="Stylet">
       <Version>1.1.22</Version>