Add onAppear event for SpiceStore

[frankois944]

Description

Add a new protocol method inside the Store for updating the Spice when the View appear.

Motivation and Context

Currently, the Spice are set only once, when the init is called.
Sometimes, some values can change during the lifetime of the application.

For example, the FCM/APNS token can change during the lifetime of the application.

So, by adding the possibility to update the value dynamically, the debug menu is more useful.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)