tests: update test-copies-chain-merge.t to not use empty files
Merging empty files is not very interesting or realistic.
# An example WSGI for use with mod_wsgi, edit as necessary
# See https://mercurial-scm.org/wiki/modwsgi for more information
# Path to repo or hgweb config to serve (see 'hg help hgweb')
config = b"/path/to/repo/or/config"
# Uncomment and adjust if Mercurial is not installed system-wide
# (consult "installed modules" path from 'hg debuginstall'):
#import sys; sys.path.insert(0, "/path/to/python/lib")
# Uncomment to send python tracebacks to the browser if an error occurs:
#import cgitb; cgitb.enable()
# enable demandloading to reduce startup time
from mercurial import demandimport; demandimport.enable()
from mercurial.hgweb import hgweb
application = hgweb(config)