Update minimum supported .NET check to 4.8

This is not updating our requirement, that apparently already changed to 4.8 as determined by testing.

Author: andyleejordan

src/PowerShellEditorServices.Hosting/EditorServicesLoader.cs

@@ -33,7 +33,7 @@ public sealed class EditorServicesLoader : IDisposable
     {
 #if !CoreCLR
         // See https://docs.microsoft.com/en-us/dotnet/framework/migration-guide/how-to-determine-which-versions-are-installed
-        private const int Net462Version = 394802;
+        private const int Net48Version = 528040;
 
         private static readonly string s_psesBaseDirPath = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
 #endif
@@ -244,7 +244,7 @@ private static void LoadEditorServices() =>
 #if !CoreCLR
         private void CheckNetFxVersion()
         {
-            _logger.Log(PsesLogLevel.Diagnostic, "Checking that .NET Framework version is at least 4.6.2");
+            _logger.Log(PsesLogLevel.Diagnostic, "Checking that .NET Framework version is at least 4.8");
             using RegistryKey key = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\Net Framework Setup\NDP\v4\Full");
             object netFxValue = key?.GetValue("Release");
             if (netFxValue == null || netFxValue is not int netFxVersion)
@@ -254,9 +254,9 @@ private void CheckNetFxVersion()
 
             _logger.Log(PsesLogLevel.Verbose, $".NET registry version: {netFxVersion}");
 
-            if (netFxVersion < Net462Version)
+            if (netFxVersion < Net48Version)
             {
-                _logger.Log(PsesLogLevel.Warning, $".NET Framework version {netFxVersion} lower than .NET 4.6.2. This runtime is not supported and you may experience errors. Please update your .NET runtime version.");
+                _logger.Log(PsesLogLevel.Warning, $".NET Framework version {netFxVersion} lower than .NET 4.8. This runtime is not supported and you may experience errors. Please update your .NET runtime version.");
             }
         }
 #endif