test-subrepo-recursion: set progress.changedelay really high

This avoids subtopics from showing up, which were introduced by my recent
change that added progress bars to hardlink clones in some cases.

tests/test-subrepo-recursion.t

@@ -260,6 +260,8 b' Enable progress extension for archive te'
   > [progress]
   > assume-tty = 1
   > delay = 0
+  > # set changedelay really large so we don't see nested topics
+  > changedelay = 30000
   > format = topic bar number
   > refresh = 0
   > width = 60