WIP: Update @types/express.
Created by: creachadair
yarn --cwd lsif add @types/express yarn --cwd lsif add @types/body-parser yarn --cwd lsif add @types/express-serve-static-core yarn --cwd lsif add @types/serve-static
After doing this, yarn --cwd lsif run build works without error.
An attempt at fixing #8775 CI break.