Fix red develop dd674ccd7371

The merge lane found `develop` red at `dd674ccd737106688e7915698be7ea70427a0c5c` on its own: no queued PR merges until it is fixed. Failing (tests and gate stages): - `tests/test_virtual_nodes.py::test_a_regular_nodes_bootstrap_is_byte_identical_to_before_hosts_existed` - `api-unit-dc-test` The whole gate log: artifact `12118` on lane task 11255. Make `develop` pass its full gate again. Open a PR as usual: the merge lane merges a PR that fixes some of these and adds no failure even while `develop` is red.

Already fixed: Task 11248 (PR #7331) re-pinned the stale bootstrap digests after dd674cc; the failing test passes on current develop (3 passed). No PR needed. Memory: none applied.