Update translation of Chinese

[S1ngS1ng]

Query

Here is the query I use in https://graphiql.stateofjs.com:

query GetLocaleData {
  locale(localeId: "zh-Hans") {
    untranslatedKeys
  }
}

Progress

Verified and updated till blocks.entity.github_link

Notes

Not translated

• user_info.gender.description: Unfortunately, I can't really come up with a good translation for this. CC @scarsu @mingjunlu @ymcheung @TIOvOIT do you have any suggestions, please?
• picks.*.(bio/description) in state_of_js_2020.yml since it is marked as TODO. @SachaG Lemme know when it is finalized please

Identical with English

The following tokens are already included in the Chinese translation. The content is identical to that in English (e.g. it won't make sense that we translate MDN or GitHub):

• options.years_of_experience.*.short
• options.company_size.*.short
• options.job_title.cto and options.form_factors.tv could be translated into Chinese. But CTO and TV should be commonly recognized as well
• general.state_of_css_link could be translated into Chinese. Consider this as a brand, I'd rather leave it untouched. Lemme know your thoughts please @SachaG
• features.mdn_link and features.mdn_link
• tools.github_link, tools.github_stars, tools.npm_link and blocks.entity.github_link
• share.block.twitter_text
• sections.css_in_js.title
• Most of features.* in state_of_css.yml
• options.units.*
• options.pseudo_elements.*
• options.tree_document_structure.*
• options.links_urls.*
• options.interaction.*
• options.form_controls.*
• features/*, array_prototype_flat

Added/Updated

• The whole state_of_css_2020.yml is missing in zh-Hans (Still WIP, 90% done)
• general.no_closed_surveys, general.preview_surveys and general.no_preview_surveys
• notfound.title and notfound.description
• options.industry_sector.*
• features.knowledge_score
• blocks.tools_quadrant.description and blocks.tools_quadrant.note are renamed from blocks.tools_quadrant.satisfaction.description and blocks.tools_quadrant.satisfaction.note. Slight rephrase and updated blocks.tools_quadrant.interest.description accordingly
• features.blend_modes.description
• features.* in state_of_css.yml: add original for those already translated
• features_others.combinators: Use full-width symbols
• options.combinators.*: use translation from MDN
• options.attributes: rephrase
• options.links_urls.link_visited
• options.form_controls.*: partial update
• environments.css_for_print.*: Needs review since I haven't found any solid resource for this translation @SachaG
• Added opinions_others.currently_missing_from_css.others.note

Question

• @SachaG I noticed that the locale of zh-Hans/state_of_css.yml is still showing en-US and I changed it to zh-Hans. Lemme know if that was expected and I'll revert it
• @SachaG It seems like picks.sachagreif.description is missing a link of the blog post by Amelia Wattenberger. Same happens with other picks as well. Are picks still WIP?

[S1ngS1ng]

@SachaG All done and ready for review. Please feel free to include anyone that could help review this PR and I'll address the changes as soon as I can.