Update Node.js to 20.x in Dockerfile (#6099)

* Update Node.js to 20.x in Dockerfile

* Update Node.js types and engines entry to 20.x

* Update Node.js version in .nvmrc

* Use node version from .nvmrc in linting job

* Use Type Assertion for clearTimeout

src/view/com/util/List.web.tsx

@@ -468,7 +468,7 @@ let Row = function RowImpl<ItemT>({
             }
           } else {
             if (intersectionTimeout.current) {
-              clearTimeout(intersectionTimeout.current)
+              clearTimeout(intersectionTimeout.current as NodeJS.Timeout)
               intersectionTimeout.current = undefined
             }
           }