Fixed an issue where Target session Id was not being persisted on app close and relaunch.

[swarna04]

Description

Ref: [MOB-15298]

Fixed an issue where if the app is closed before session expiry, a new session Id is generated. This was happening because the generated session Id, on app launch, was not being persisted because of an issue in the code.

Related Issue

Motivation and Context

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• [x] 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 change)

Checklist:

• [x] I have signed the Adobe Open Source CLA.
• [x] My code follows the code style of this project.
• [x] My change requires a change to the documentation.
• [x] I have updated the documentation accordingly.
• [x] I have read the CONTRIBUTING document.
• [x] I have added tests to cover my changes.
• [x] All new and existing tests passed.