monotone: fix a bogus _() wrapper that was caught when formatting code

There was a spurious space after `debug`, which hid the _() inside
ui.debug() from check-code. Sigh.

While here, wrap things more concisely.

Differential Revision: https://phab.mercurial-scm.org/D6338

hgext/convert/monotone.py

@@ -284,8 +284,8 b' class monotone_source(common.converter_s'
                     # d2 => d3
                     ignoremove[tofile] = 1
             for tofile, fromfile in renamed.items():
-                self.ui.debug (_("copying file in renamed directory "
-                                 "from '%s' to '%s'")
+                self.ui.debug(
+                    "copying file in renamed directory from '%s' to '%s'"
                                % (fromfile, tofile), '\n')
                 files[tofile] = rev
                 copies[tofile] = fromfile
@@ -370,4 +370,3 b' class monotone_source(common.converter_s'
             self.mtnwritefp = None
             self.mtnreadfp.close()
             self.mtnreadfp = None
-