CI: Cypress e2e failures caused by Chrome 155 runner update #186

GitHub automatically updated the Ubuntu runner image to Chrome 155 on Oct 13. Since then, all scheduled builds and PRs are failing on the same commit (d4868c36a8).

Evidence:

• 26 jobs on Chrome 154 passed; 12 jobs on Chrome 155 failed.
• The new browser exposes a race condition in our Cypress helper (cypress/support/commands.ts:101-103).
• The auto-rerun job also fails due to missing permissions.

Proposed Fix:
Port upstream DSpace PR DSpace#6378. Switch CI to use browser-actions/setup-chrome@v2 with chrome-for-testing, make the DiscoJuice wait conditional