Add a function to check if target_word contains CJK characters

[ahmad-alkadri]

This PR is linked to Issue #904 which shows that Whoogle results do not render bold all of target words if they are Chinese characters.

Further investigations show similar behavior for Japanese (hiragana, katakana, kanji), and Korean (hangul syllables, hangul jamo) characters: not all of the words displayed on the result page are bolded.

To handle this, a function was added to check if target_word in bold_search_terms.replace_any_case contains Chinese, Korean, or Japanese characters and apply the regex that doesn't check for whitespace. This way, each search term would be bolded differently.

Screenshots of the search results after the commits linked to this PR:

[benbusby]

Looks good to me, thanks for taking care of this! I had just one idea for a way to make the code a little easier to modify in the future (if needed), let me know your thoughts.

[ahmad-alkadri]

Looks good to me, thanks for taking care of this! I had just one idea for a way to make the code a little easier to modify in the future (if needed), let me know your thoughts.

Hi @benbusby; thanks for your input! I agree with your suggestion, and I've tested it also on several queries:

It seems to work well. So I've committed it to the branch; would you like to test it also? I'm available for other follow-up discussions/modifications on this.

[benbusby]

Looks great, thank you again!