Flipper App 1.7.1.1758

Add core storage (#955)

      **Background**

We are now using a platform-specific version of flipper storage
throughout the project.
This is not correct. As part of the overall migration of the project to
KMP, we are gradually moving to okio + core:storage

**Changes**

- Add `core:storage`
- Add `core:atomicfile`

**Test plan**

Try launch tests and also migrating from old version of application