Allow '0' as username with Jabber notifications

It seems that the part of the following commit where we check that

IF AUTHOR_NAME !== ''

instead of

IF AUTHOR_NAME

https://github.com/phpbb/phpbb/commit/2ce83fce1eb3031b71a54a555b8766f35d8b6ac7

is missing from the next two files:
language/en/email/short/topic_notify.txt
language/en/email/short/newtopic_notify.txt

If this is indeed a bug, and is not omitted intentionally for the Jabber system, to which branches needs to be merged?