filter out polly and redis (#4218)

We don't publish those documents, so the xrefs should not be links.

Author: BillWagner

xml/_filter.xml

@@ -165,5 +165,14 @@
       <typeFilter name="DependencyInjectionSpecificationTests" expose="false" />
       <typeFilter name="DependencyInjectionSpecificationTests.CreateInstanceFunc" expose="false" />
     </namespaceFilter>
+    <namespaceFilter name="StackExchange.Redis">
+      <typeFitler name="*" expose="false" />
+    </namespaceFilter>
+    <namespaceFilter name="Polly">
+      <typeFilter name="*" expose="false" />
+    </namespaceFilter>
+    <namespaceFilter name="Polly.Registry">
+      <typeFilter name="*" expose="false" />
+    </namespaceFilter>
   </apiFilter>
 </filter>