systemctl: show: use EnvironmentFiles= instead of EnvironmentFile=

EnvironmentFile= is used in the unit file, but in the dbus,
the related field name is EnvironmentFiles=.
As the other variables, let's use the field name instead of the name
used in the unit file setting.

src/systemctl/systemctl.c

@@ -4870,7 +4870,7 @@ static int print_property(const char *name, sd_bus_message *m, const char *conte
                                 return bus_log_parse_error(r);
 
                         while ((r = sd_bus_message_read(m, "(sb)", &path, &ignore)) > 0)
-                                print_prop("EnvironmentFile", "%s (ignore_errors=%s)", path, yes_no(ignore));
+                                print_prop(name, "%s (ignore_errors=%s)", path, yes_no(ignore));
 
                         if (r < 0)
                                 return bus_log_parse_error(r);