Update PublishDocsRules for Navigation 2.1.0-alpha01

Test: ./gradlew bOS
Change-Id: I776f259eb2e1996e0a444a8000f4193077eb9c99
diff --git a/buildSrc/src/main/kotlin/androidx/build/PublishDocsRules.kt b/buildSrc/src/main/kotlin/androidx/build/PublishDocsRules.kt
index 60e0de9..f733ca8 100644
--- a/buildSrc/src/main/kotlin/androidx/build/PublishDocsRules.kt
+++ b/buildSrc/src/main/kotlin/androidx/build/PublishDocsRules.kt
@@ -77,7 +77,7 @@
     prebuilts(LibraryGroups.MEDIA2, "1.0.0-alpha03")
     prebuilts(LibraryGroups.MEDIAROUTER, "1.1.0-alpha02")
     ignore(LibraryGroups.NAVIGATION.group, "navigation-testing")
-    prebuilts(LibraryGroups.NAVIGATION, "2.0.0-rc02")
+    prebuilts(LibraryGroups.NAVIGATION, "2.1.0-alpha01")
     prebuilts(LibraryGroups.PAGING, "2.1.0")
     prebuilts(LibraryGroups.PALETTE, "1.0.0")
     prebuilts(LibraryGroups.PERCENTLAYOUT, "1.0.0")