Known bug: TemplateVM updates failing (fix in testing)

[Andrew David Wong]

Dear Qubes Community,

We are aware of a bug that prevents TemplateVMs from updating normally:

https://github.com/QubesOS/qubes-issues/issues/6188

When attempting to update a TemplateVM, this bug results in traceback
mentioning qubes-vm-connector, like this:

```
<vm_name>:
----------
_error:
Failed to return clean data
retcode:
1
stderr:
Traceback (most recent call last):
File "/usr/lib/qubes-vm-connector/ssh-wrapper/ssh", line
101, in <module>
sys.exit(main())
File "/usr/lib/qubes-vm-connector/ssh-wrapper/ssh", line
94, in main
return ssh(args)
File "/usr/lib/qubes-vm-connector/ssh-wrapper/ssh", line
29, in ssh
assert args[1] == '/bin/sh'
AssertionError
stdout:
```

This bug has already been fixed, but the fix is currently in testing. If
you wish to help us test this fix, please see the comments on the issue
linked above for specific instructions, package names, and package
versions for each Qubes release and TemplateVM.

For more information about testing updates, including the expected
timeline for updates to migrate from testing to stable, please see:

https://www.qubes-os.org/doc/testing/#updates

--
Andrew David Wong (Axon)
Community Manager, Qubes OS
https://www.qubes-os.org