[native] Bump expo and expo-image

Summary: Resolves ENG-3752. Bumped expo-image to 1.2.0 - version that supports thumbhash. This also required bumping expo package in order to bump its dependency expo-modules-core to 1.1.1.

Test Plan: Built both iOS and Android. Played around - photo messages and avatars are still displayed correctly. Added dummy placeholder={{ thumbhash }} prop to Image component to ensure thumbhash works.

Reviewers: ashoat, atul

Reviewed By: ashoat, atul

Subscribers: tomek

Differential Revision: https://phab.comm.dev/D7748