fix #3554 duplicated first line of details line in Logviewer

[ssahara]

fix #3554 duplicated printing (see bellow) of first details block of a log record generated dokuwiki\Logger::error()

2021-11-24 02:18:59Error: Object of class dokuwiki\ChangeLog\PageChangeLog could not be converted to string /home/core/DokuWiki/revsionHandle3/inc/ChangeLog/ChangeLog.php(588)
    #0 /home/core/DokuWiki/revsionHandle3/inc/ChangeLog/ChangeLog.php(39): dokuwiki\ChangeLog\ChangeLog->getCurrentRevisionInfo()
    #0 /home/core/DokuWiki/revsionHandle3/inc/ChangeLog/ChangeLog.php(39): dokuwiki\ChangeLog\ChangeLog->getCurrentRevisionInfo()
    #1 /home/core/DokuWiki/revsionHandle3/inc/common.php(248): dokuwiki\ChangeLog\ChangeLog->__construct()
    #2 /home/core/DokuWiki/revsionHandle3/doku.php(93): pageinfo()
    #3 {main} 

[splitbrain]

fixed with b9a4556