[Fix] Fix setting class on style field
[Fix] Fix setting class on style field

Issue: #1492

AlexeySa/rspamd,AlexeySa/rspamd,AlexeySa/rspamd,AlexeySa/rspamd,AlexeySa/rspamd,AlexeySa/rspamd,AlexeySa/rspamd,AlexeySa/rspamd,AlexeySa/rspamd