Removed unused mitigation topics (dotnet#3302)

* Removed unused mitigation topics

* Removed duplicate redirection entry

Author: Ron Petrusha

.openpublishing.redirection.json

@@ -498,6 +498,50 @@
             "source_path": "docs/framework/migration-guide/net-compatibility-diagnostics.md",
             "redirect_url": "/dotnet/framework/migration-guide/application-compatibility"
         },
+        {
+            "source_path": "docs/framework/migration-guide/mitigation-claimsidentity-constructor.md",
+            "redirect_url": "/dotnet/framework/migration-guide//retargeting/4.6.1-4.6.2"
+        },
+        {
+            "source_path": "docs/framework/migration-guide/mitigation-cspparameters-parentwindowhandle-expects-an-hwnd.md",
+            "redirect_url": "/dotnet/framework/migration-guide/retargeting/4.6.2-4.7"
+        },
+        {
+            "source_path": "docs/framework/migration-guide/migration-guide/mitigation-culture-and-asynchronous-operations.md",
+            "redirect_url": "/dotnet/framework/migration-guide/retargeting/4.5.2-4.6"
+        },
+        {
+            "source_path": "docs/framework/migration-guide/migration-guide/mitigation-culture-and-dispatcher-operations-in-wpf-apps.md",
+            "redirect_url": "/dotnet/framework/migration-guide/retargeting/4.5.2-4.6"
+        },
+        {
+            "source_path": "docs/framework/migration-guide/migration-guide/mitigation-default-authorizationcontext.md",
+            "redirect_url": "/dotnet/framework/migration-guide/retargeting/4.5.2-4.6"
+        },
+        {  
+            "source_path": "docs/framework/migration-guide/migration-guide/mitigation-eventsource-writeevent-method-calls.md",
+            "redirect_url": "/dotnet/framework/migration-guide/runtimef/4.5-4.5.1"
+        },
+        {  
+            "source_path": "docs/framework/migration-guide/migration-guide/mitigation-grid-control.md",
+            "redirect_url": "/dotnet/framework/migration-guide/retargeting/4.6.2-4.7"
+        },
+        {  
+            "source_path": "docs/framework/migration-guide/migration-guide/mitigation-horizontal-scrolling-and-virtualization.md",
+            "redirect_url": "/dotnet/framework/migration-guide/runtime/4.6.1-4.6.2"
+        },
+        {  
+            "source_path": "docs/framework/migration-guide/migration-guide/mitigation-long-path-support.md",
+            "redirect_url": "/dotnet/framework/migration-guide/retargeting/4.6.1-4.6.2"
+        },
+        {  
+            "source_path": "docs/framework/migration-guide/migration-guide/mitigation-memberdescriptor-equals.md",
+            "redirect_url": "/dotnet/framework/migration-guide/retargeting/4.6.1-4.6.2"
+        },
+        {  
+            "source_path": "docs/framework/migration-guide/migration-guide/mitigation-minfreememorypercentagetoactiveservice-configuration-setting.md",
+            "redirect_url": "/dotnet/framework/migration-guide/runtime/4.5-4.5.1"
+        },
         {
             "source_path": "docs/framework/migration-guide/retargeting-changes-in-the-net-framework-4-5-1.md",
             "redirect_url": "/dotnet/framework/migration-guide/retargeting/index"