Skip URL-less mention terms in Object\Post::getDefaultText
Skip URL-less mention terms in Object\Post::getDefaultText

- Address https://github.com/friendica/friendica/issues/10167#issuecomment-830859710
- Added logging to troubleshoot deeper issue

friendica/friendica,annando/friendica,annando/friendica,tobiasd/friendica,annando/friendica,tobiasd/friendica,friendica/friendica,tobiasd/friendica,annando/friendica,friendica/friendica,friendica/friendica,tobiasd/friendica,tobiasd/friendica,annando/friendica,friendica/friendica