[H/3] Enable few disabled H/3 cookie tests (#120363)

Author: ManickaP

src/libraries/Common/tests/System/Net/Http/HttpClientHandlerTest.Cookies.cs

@@ -300,12 +300,6 @@ await LoopbackServerFactory.CreateServerAsync(async (server, url) =>
         [SkipOnPlatform(TestPlatforms.Browser, "CookieContainer is not supported on Browser")]
         public async Task GetAsyncWithRedirect_SetCookieContainer_CorrectCookiesSent()
         {
-            if (UseVersion == HttpVersion30)
-            {
-                // [ActiveIssue("https://github.com/dotnet/runtime/issues/56870")]
-                return;
-            }
-
             const string path1 = "/foo";
             const string path2 = "/bar";
             const string unusedPath = "/unused";
@@ -481,12 +475,6 @@ await LoopbackServerFactory.CreateServerAsync(async (server, serverUrl) =>
         [SkipOnPlatform(TestPlatforms.Browser, "CookieContainer is not supported on Browser")]
         public async Task GetAsync_Redirect_CookiesArePreserved()
         {
-            if (UseVersion == HttpVersion30)
-            {
-                // [ActiveIssue("https://github.com/dotnet/runtime/issues/56870")]
-                return;
-            }
-
             HttpClientHandler handler = CreateHttpClientHandler();
 
             string loginPath = "/login/user";
@@ -617,12 +605,6 @@ await LoopbackServerFactory.CreateServerAsync(async (server, url) =>
         [SkipOnPlatform(TestPlatforms.Browser, "CookieContainer is not supported on Browser")]
         public async Task GetAsyncWithRedirect_ReceiveSetCookie_CookieSent()
         {
-            if (UseVersion == HttpVersion30)
-            {
-                // [ActiveIssue("https://github.com/dotnet/runtime/issues/56870")]
-                return;
-            }
-
             const string path1 = "/foo";
             const string path2 = "/bar";