Merge branch 'how_to_contribute_2' into 'master'

main/assets/css/extra.css

main/assets/js/hotjar.js

mkdocs.yml

topics/about-us/docs/contribute/assets/overview.png

topics/about-us/docs/contribute/assets/signpost.png

topics/about-us/docs/contribute/assets/standard.png

...us/docs/contribute/contributing/set-up-and-work-localy.md

...-us/docs/contribute/contributing/work-within-gitlab-ui.md

topics/about-us/docs/contribute/overview.md

topics/about-us/docs/contribute/style-guide/style.md

...about-us/docs/contribute/style-guide/writing-practices.md

topics/about-us/docs/contribute/style.md

topics/about-us/docs/contribute/technical-details.md

topics/about-us/mkdocs.yml