tests/test-demandimport.py.out

test-serve: make the 'listening at *' lines optional

The daemonized serve process doesn't print these lines out (see 448d0c452140).
I was able to get it to with the following hack:

 diff --git a/mercurial/win32.py b/mercurial/win32.py
 --- a/mercurial/win32.py
 +++ b/mercurial/win32.py
 @@ -418,6 +418,11 @@
          return str(ppid)

  def spawndetached(args):
 +
 +    import subprocess
 +    return subprocess.Popen(args, cwd=pycompat.getcwd(), env=encoding.environ,
 +                            creationflags=subprocess.CREATE_NEW_PROCESS_GROUP).pid
 +
      # No standard library function really spawns a fully detached
      # process under win32 because they allocate pipes or other objects
      # to handle standard streams communications. Passing these objects

However, MSYS translates --prefixes starting with '/' to 'C:/MinGW/msys/1.0',
which changes the output.  The output isn't so important that I want to spend a
bunch of time on this, and risk breaking some subtle behavior of `hg serve -d`
with the more complicated code.

os = <unloaded module 'os'>
os.system = <built-in function system>
os = <module 'os' from '?'>
util = <unloaded module 'util'>
util.system = <function system at 0x?>
util = <module 'mercurial.util' from '?'>
util.system = <function system at 0x?>
hgweb = <unloaded module 'hgweb'>
hgweb_mod = <unloaded module 'hgweb_mod'>
hgweb = <module 'mercurial.hgweb' from '?'>
fred = <unloaded module 're'>
re = <unloaded module 'sys'>
fred = <unloaded module 're'>
fred.sub = <function sub at 0x?>
fred = <proxied module 're'>
re = <unloaded module 'sys'>
re.stderr = <open file '<whatever>', mode 'w' at 0x?>
re = <proxied module 'sys'>
contextlib = <unloaded module 'contextlib'>
contextlib.unknownattr = ImportError: cannot import name unknownattr
__import__('contextlib', ..., ['unknownattr']) = <module 'contextlib' from '?'>
hasattr(contextlibimp, 'unknownattr') = False
node = <module 'mercurial.node' from '?'>