fix: detach useScrolling listener from observed element

[ArianMoeini]

Description

useScrolling adds its scroll listener to ref.current, but cleanup reads the ref again. If it points to another element or becomes null before unmount, the original listener stays attached. Capture the observed element and detach from that same element.

This addresses a different cleanup case from the pending timer fix in #2698.

Type of change

• Bug fix

Checklist

• Read the Contributing Guide
• Perform a code self-review
• Cover changes with tests (ref replaced and ref cleared)
• Ensure the test suite passes (yarn test: 77 suites, 494 tests)
• Make sure code lints (yarn lint: 0 errors, 96 existing warnings)
• Make sure types are fine (yarn lint:types)