Docs: Adds a redirect to make it easier to access Performance section on DAC.

d.android.com/performance will now take you to d.android.com/topic/performance

Change-Id: I56bc85f156a9cb05a664fbf361eb5b99e153b419

docs/html/_redirects.yaml

@@ -25,6 +25,8 @@ redirects:
   to: /topic/libraries/support-library/index.html
 - from: /billions
   to: /topic/billions/index.html
+- from: /performance
+  to: /topic/performance/index.html
 - from: /tools/extras/support-library.html
   to: /topic/libraries/support-library/index.html
 - from: /training/basics/fragments/support-lib.html