flaky CI Android: sshd doesn't start?

[BenWiederhake]

The CI step Create and cache emulator image of the CI processes Test builds (ubuntu-latest, 4, 4096, 28, google_apis_playstore, x86) and Test builds (ubuntu-latest, 4, 8192, 28, google_apis_playstore, x86_64) currently fail, probably for all PRs.

This is a real problem: It affects at least #6567 (https:/uutils/coreutils/actions/runs/9935343851/job/27441336763#step:11:558 and https:/uutils/coreutils/actions/runs/9935343851/job/27441337288#step:11:576), and #6564 (https:/uutils/coreutils/actions/runs/9935800830/job/27442703141?pr=6564 and https:/uutils/coreutils/actions/runs/9935800830/job/27442702678?pr=6564), and probably many more PRs.

Typical log output:

/sdcard/sshd.probe
==================================== SUMMARY ===================================
Command: sshd; echo $? > /sdcard/sshd.probe
Finished in 3 seconds.
Output was:
+ sshd
+ echo 0
Return code: 0
================================================================================
take screenshot: /home/runner/work/coreutils/coreutils/output/072935UTC_run_termux_command_finished_normally_screen.png
[2024-07-15 07:29:35] Warning: Permanently added '[127.0.0.1]:9022' (ED25519) to the list of known hosts.
[2024-07-15 07:29:35] Connection closed by 127.0.0.1 port 9022
failed to setup ssh connection
Error: The process '/usr/bin/sh' failed with exit code 1
Terminate Emulator
  /usr/local/lib/android/sdk/platform-tools/adb -s emulator-5554 emu kill
  OK: killing emulator, bye bye
  OK
  INFO    | Wait for emulator (pid 2139) 20 seconds to shutdown gracefully before kill;you can set environment variable ANDROID_EMULATOR_WAIT_TIME_BEFORE_KILL(in seconds) to change the default value (20 seconds)
INFO    | Saving with gfxstream=1
ERROR   | stop: Not implemented
WARNING | Emulator client has not yet been configured.. Call configure me first!

This particular error message reads like sshd shuts down immediately after forking into the background. No idea what's going on.