Fix red develop 9da925d7d8d7

The merge lane found `develop` red at `9da925d7d8d7068d863ddae60e934b01473f43b3` on its own: no queued PR merges until it is fixed. Failing (tests and gate stages): - `shared-accounts-mount-selftest` The whole gate log: artifact `12470` on lane task 11458. 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.

Fixed red develop (shared-accounts-mount-selftest): converge tests assumed /home/jaah/.jaah doesn't exist, but it is real on the lane host (user jaah). Tests now use a JAAH_HOME no host has. 61/61 pass, quick gate green; PR #7400 queued. Memory: none applied.