Merge production MR to launch Japanese docs site

• Create an MR to launch the Japanese docs site in production, in the docs-gitlab-com project. Use this MR to launch the Japanese docs site: Japanese Documentation (gitlab-org/technical-writing/docs-gitlab-com!1371 - merged)
• Configure the necessary Hugo settings (should be similar to the QA environment MR: Japanese Documentation (gitlab-org/technical-writing/docs-gitlab-com!1371 - merged))
• Assign to the engineer on the Technical Writing team for review
• Close the QA environment MR: gitlab-org/technical-writing/docs-gitlab-com!1371 (merged)
• Create another MR to disable the JA docs site (in case something goes awry with launch)