Update dependency libsass to ^0.20.0

This MR contains the following updates:

Package	Type	Update	Change
libsass	dependencies	minor	^0.19.2 -> ^0.20.0

---

Renovate configuration

Schedule: At any time (no schedule defined).

Automerge: Disabled by config. Please merge this manually once you are satisfied.

Rebasing: Whenever MR becomes conflicted, or you tick the rebase/retry checkbox.

Ignore: Close this MR and you won't be reminded about this update again.

---

• If you want to rebase/retry this MR, check this box

---

This MR has been generated by Renovate Bot.