Tests | Refactor Login Test and Reuse Global Authentication Settings

[dujes8]

Changes Made:

• Refactored the login test
• Implemented setupAuth functionality, which is now defined globally inside the Playwright configuration (this setup is reused across all test suites)
• Removed redundant test.use calls from individual test suites

Benefits:

• Eliminated the need for unnecessary test.use calls inside each test suite
• Centralized authentication setup, improving code organization and reducing redundancy

Additional:

• Fix failing 'Document public link revoke' test (expect was placed on the wrong place inside test)