Revert "doc: import() is supported now" by MylesBorins · Pull Request #18141 · nodejs/node

This reverts commit 977fb13.

This should not have landed on v9.x which does not yet
support the feature

PR-URL: #18141
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>
Reviewed-By: Tiancheng "Timothy" Gu <timothygu99@gmail.com>
Reviewed-By: Franziska Hinkelmann <franziska.hinkelmann@gmail.com>
Reviewed-By: Khaidi Chu <i@2333.moe>
Reviewed-By: Evan Lucas <evanlucas@me.com>
Reviewed-By: James M Snell <jasnell@gmail.com>