Update "how to search" page with information about Arabic/JA exact matches

[blms]

Task for the content team.

On the How To Search page, there currently isn't any mention of the fact that searching in Arabic will also bring up Judaeo-Arabic results.

• Might be worth mentioning that this is possible
• After Bracket and other character search is functioning unpredictably  #1286, we should also mention that using exact search with double quotes around an Arabic term will only produce Arabic results
  • We can also mention here that when searching for words with transcription sigla in them, you have to remove the sigla from your search query; if you want to match only those documents which contain the exact sigla, surround the term with the sigla in double quotes like "sig[l]a"
• After Some partial search results in description not boosted by relevancy #1335, we can also mention about highlights and searches with dashes