fix: fix PostConfigureOAuth2IntrospectionOptions with named options

Author: NatMarchand

src/OAuth2IntrospectionExtensions.cs

@@ -50,9 +50,9 @@ public static AuthenticationBuilder AddOAuth2Introspection(this AuthenticationBu
         /// <returns></returns>
         public static AuthenticationBuilder AddOAuth2Introspection(this AuthenticationBuilder builder, string authenticationScheme, Action<OAuth2IntrospectionOptions> configureOptions)
         {
-            builder.Services.AddHttpClient(OAuth2IntrospectionDefaults.BackChannelHttpClientName);
-            
-            builder.Services.TryAddEnumerable(ServiceDescriptor.Singleton<IPostConfigureOptions<OAuth2IntrospectionOptions>, PostConfigureOAuth2IntrospectionOptions>());
+            builder.Services.AddHttpClient(OAuth2IntrospectionDefaults.BackChannelHttpClientName);
+
+            builder.Services.Add(ServiceDescriptor.Singleton<IPostConfigureOptions<OAuth2IntrospectionOptions>>(p => ActivatorUtilities.CreateInstance<PostConfigureOAuth2IntrospectionOptions>(p, authenticationScheme)));
             return builder.AddScheme<OAuth2IntrospectionOptions, OAuth2IntrospectionHandler>(authenticationScheme, configureOptions);
         }
     }

src/PostConfigureOAuth2IntrospectionOptions.cs

@@ -13,17 +13,24 @@ namespace IdentityModel.AspNetCore.OAuth2Introspection
 {
     internal class PostConfigureOAuth2IntrospectionOptions : IPostConfigureOptions<OAuth2IntrospectionOptions>
     {
+        private readonly string _name;
         private readonly IDistributedCache _cache;
         private readonly IHttpClientFactory _httpClientFactory;
 
-        public PostConfigureOAuth2IntrospectionOptions(IHttpClientFactory httpClientFactory, IDistributedCache cache = null)
+        public PostConfigureOAuth2IntrospectionOptions(string name, IHttpClientFactory httpClientFactory, IDistributedCache cache = null)
         {
+            _name = name;
             _cache = cache;
             _httpClientFactory = httpClientFactory;
         }
 
         public void PostConfigure(string name, OAuth2IntrospectionOptions options)
         {
+            if (name != _name)
+            {
+                return;
+            }
+
             options.Validate();
 
             if (options.EnableCaching && _cache == null)