fixes some markup issues in the js style guide docs

See the general Documentation guidelines http://docs.gitlab.com/ce/development/doc_styleguide.html

What does this MR do?

fixes some layout issues at https://docs.gitlab.com/ce/development/fe_guide/style_guide_js.html

issues:

• https://docs.gitlab.com/ce/development/fe_guide/style_guide_js.html#modules-imports-and-exports bullet 1 second paragraph is not properly indented
• https://docs.gitlab.com/ce/development/fe_guide/style_guide_js.html#alignment: bullet 1 layout is garbled.
• https://docs.gitlab.com/ce/development/fe_guide/style_guide_js.html#props: bullet 3 is not properly indented
• https://docs.gitlab.com/ce/development/fe_guide/style_guide_js.html#ordering: bullet 1 is not properly indented