[ENG-9260] | fix(google-drive): resolve file list refresh and intermittent 403 errors

[sh-andriy]

• Ticket: []
• Feature flag: n/a

Purpose

PR Summary:

Problem: After configuring Google Drive addon, two issues occurred:

1. Files added via "Add from Drive" button didn't appear immediately - required page reload (F5)
2. Intermittent 403 "Forbidden" errors when opening Google Drive picker

Solution:

• Fixed updateFilesList callback losing this context by converting it to an arrow function property
• OAuth token now refreshes each time the picker opens instead of only once during component initialization

Result: Files now appear immediately after selection, and 403 errors should be eliminated since a fresh token is fetched before each picker open.

Summary of Changes

Screenshot(s)

Side Effects

QA Notes