DDLS-370 Non primary accounts should get redirect message instead of add client

[iqpalm]

Purpose

Non primary accounts that have no active clients associated with them are taken to the add client screen instead of the ‘use your other account’ screen.

Fixes DDLS-370

Approach

Added in test to cover the scenario where secondary account with discharged client tries to login and is logged out and flash message appears with primary email address to login with.

Learning

Any tips and tricks, blog posts or tools which helped you. Plus anything notable you've discovered about DigiDeps

Checklist

• I have performed a self-review of my own code
• I have updated documentation (Confluence/ADR/tech debt doc) where relevant
• I have added tests to prove my work
• The product team have approved these changes
• I have checked my work for potential security issues and refered to the OWASP top 10

Frontend

• I have run an in-browser accessibility test (e.g. WAVE, Lighthouse)
• There are no deprecated CSS classes noted in the profiler
• Translations are used and the profiler doesn't identify any missing
• Any links or buttons added are screen reader friendly and contextually complete
• If adding GA events, I have updated or checked the existing category or label values