[IOAPPX-260] Update Avatar component, deprecate shape prop

[dmnplb]

Short description

This PR updates the Avatar component with an inner rounded wrapper to handle edge cases (entity logos without rounded shapes, etc...). It also deprecates the shape prop because the rounded square is the only accepted variant.

List of changes proposed in this pull request

• Add two different radius values: 8 for small version, 12 for medium one
• Link the shape radius value to the AnimatedMessageCheckbox component
• Deprecate shape prop using JSDoc syntax
• [Extra] Add react-native-easing-gradient as peer dependency

Preview

double-radius-values.mp4

How to test

1. Launch the example app
2. Go to the Logos page