test_gnc_setlocale: add missing whitespaces to diagnostic message

libgnucash/engine/test/test-gnc-date.c

@@ -487,10 +487,10 @@ test_gnc_setlocale (int category, gchar *locale)
             return;
     }
     g_fprintf (stderr, "There are some differences between distros in the way they name"
-              "locales, and this can cause trouble with the locale-based"
-              "formatting. If you get the assert in this function, run locale -a"
-              "and make sure that en_US, en_GB, and fr_FR are installed and that"
-              "if a suffix is needed it's in the suffixes array.");
+              " locales, and this can cause trouble with the locale-based"
+              " formatting. If you get the assert in this function, run locale -a"
+              " and make sure that en_US, en_GB, and fr_FR are installed and that"
+              " if a suffix is needed it's in the suffixes array.");
     g_assert_not_reached ();
 }
 /* timespecCanonicalDayTime