test-serve: kill daemons before deleting the access and error logs

On Windows, `rm` will fail with 'Permission denied' if another process has it
open.  It looks like the rollback test was missing the kill entirely.

tests/test-largefiles-wireproto.t

@@ -441,7 +441,7 b' a large file from the server rather than'
   1 largefiles updated, 0 removed
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
+  $ killdaemons.py
   $ rm hg.pid access.log
-  $ killdaemons.py
 
 #endif

tests/test-rollback.t

@@ -148,6 +148,8 b' presents the correct tip changeset:'
   working directory now based on revision 0
   $ hg id default
   791dd2169706
+
+  $ killdaemons.py
 #endif
 
 update to older changeset and then refuse rollback, because