cmd/golangorg: update testdata to match wiki contents

old wiki contained "Wiki: Index",
now it contains " Wiki: Home"

Update the "loading..." copy to match.

Change-Id: I27f5831d725dbeda8e33a5163edcbba58b8f6a38
Reviewed-on: https://go-review.googlesource.com/c/website/+/552975
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Suzy Mueller <suzmue@golang.org>
Run-TryBot: David Chase <drchase@google.com>

_content/wiki/index.md

@@ -1,5 +1,5 @@
 ---
-title: Index
+title: Home
 ---
 
 The Wiki is still loading...

cmd/golangorg/testdata/godev.txt

@@ -111,7 +111,7 @@ GET https://go.dev/doc/security/
 body contains Security
 
 GET https://go.dev/wiki/
-body contains Go Wiki: Index
+body contains Go Wiki: Home
 body contains <i>This content is part of the <a href="/wiki/">Go Wiki</a>.</i>
 
 GET https://go.dev/wiki/Comments