Improve handling bsc#1008493 in yast2_tftp module

Once in a while we may match log needle, if error is not shown
immediately. So, move soft-failure further, so we actually try to close
dialog, and if it didn't work, we check if error is shown.

Be aware that this issue doesn't appear often, and wait_still_screen
would also do the trick, but we don't to wait for no reason.

See [poo#34072](https://progress.opensuse.org/issues/34072).

tests/console/yast2_tftp.pm

@@ -55,14 +55,17 @@ sub run {
 
     # view log
     send_key 'alt-v';                                                                     # open log window
-    assert_screen([qw(yast2_tftp_view_log_error yast2_tftp_view_log_show)]);
+    assert_screen('yast2_tftp_view_log_show');
+    send_key 'alt-c';                                                                     # close the window
+    assert_screen([qw(yast2_tftp_view_log_error yast2_tftp_closed_port)]);
     if (match_has_tag('yast2_tftp_view_log_error')) {
         # softfail for opensuse when error for view log throws out
         record_soft_failure "bsc#1008493";
-        send_key 'alt-o';                                                                 # confirm the error message
+        wait_screen_change { send_key 'alt-o' };                                          # confirm the error message
+        assert_screen('yast2_tftp_view_log_show');
+        send_key 'alt-c';                                                                 # close the window
+        assert_screen 'yast2_tftp_closed_port';
     }
-    send_key 'alt-c';                                                                     # close the window
-    assert_screen 'yast2_tftp_closed_port';
     # now finish tftp server configuration
     send_key 'alt-o';                                                                     # confirm changes
 
@@ -83,4 +86,3 @@ sub run {
 }
 
 1;
-