flair deps: make janome optional

Make janome optional and install with konoha (for JapaneseTokenizer). Based on the discussion https://github.com/flairNLP/flair/pull/3394#issuecomment-1935771503.

Feb 09 '24 16:02 himkt

Hi @helpmefindaname,

I made janome optional 533da58 and kicked the CI: https://github.com/flairNLP/flair/actions/runs/7855091132/job/21436459600

According to the result, it looks flair without janome works without any code modification (=only JapaneseTokenizer related test test_create_sentence_using_japanese_tokenizer failed). So I think it's OK to just make that optional. Can I ask you to check?

Feb 15 '24 15:02 himkt

I had in my head that it was more complicated but looking at the code again, this looks good.

Also I can clearly follow your example. Thank you for taking the time to solve this.

Feb 15 '24 15:02 helpmefindaname

@himkt thanks for improving this! And thanks @helpmefindaname for testing!

Mar 06 '24 14:03 alanakbik