persistent-nodemap: disable it unconditionally for test-http-bad-server.t

This is not relevant for the test and this will avoid a lot of variations

Differential Revision: https://phab.mercurial-scm.org/D10331

tests/test-http-bad-server.t

@@ -13,6 +13,7 b' version so behavior is deterministic.'
   > fakeversion = `pwd`/fakeversion.py
   > [format]
   > sparse-revlog = no
+  > use-persistent-nodemap = no
   > [devel]
   > legacy.exchange = phases
   > [server]