docs(managed-gitlab): note admin_mode scope requirement for Admin Mode - #1212

✓ 19:45:23.405Z  Clone repository  +16s
  ├─ ✓ 19:45:23.408Z  Update reference repository  +3s
  └─ ✓ 19:45:27.178Z  Checkout repository  +12s
ℹ 19:45:39.854Z  YFM version equals 5.43.3.
✓ 19:45:41.581Z  YFM: Public check — done  +11m 22s
  ├─ ✓ 19:45:41.587Z  Validation  +7m 32s
  │  ├─ ℹ 19:53:14.073Z  Warnings: 0 Errors: 0
  │  └─ ℹ 19:53:14.157Z  Validate log: https://server-yfm-preview.website.yandexcloud.net/d-ad9449fc-e219-47c2-a23e-ce32b83657d1/validate.combined.log
  └─ ✓ 19:53:14.157Z  Upload to storage  +3m 49s
✓ 19:57:03.957Z  Cleanup finished  +4s