enable our redesign banner (mdn#5348)

build(deps): bump lxml from 4.6.1 to 4.6.5 in /testing/integration (m…

…dn#5346)

Redesign (mdn#5337)

MDN redesign

Co-authored-by: Kasey Kelly <[email protected]>
Co-authored-by: Chris Beaven <[email protected]>
Co-authored-by: Michael Trythall <[email protected]>
Co-authored-by: Luciano Ratamero <[email protected]>
Co-authored-by: Nicolas Lara <[email protected]>
Co-authored-by: Guy Sleigh <[email protected]>
Co-authored-by: Schalk Neethling <[email protected]>

build(deps): bump dayjs from 1.10.7 to 1.10.8 (mdn#5340)

build(deps-dev): bump html-validate from 6.3.2 to 6.5.0 (mdn#5335)

build(deps): bump boto3 from 1.21.3 to 1.21.8 in /deployer (mdn#5334)

build(deps): bump actions/setup-node from 2.5.1 to 3 (mdn#5321)

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

(fix:testing) bump nodejs to v14 (mdn#5328)

docs(es): add Spanish translations into optionalGeneric file (mdn#5246)

- [x] add support for Spanish on `optionalGeneric`

docs(es): add Spanish translation into addon sidebar (mdn#5248)