Misleading message from backup step of deploy

```
Backup old directories ...
Moving C:\Instrument\Apps\EPICS to C:\data\old\ibex_backup_2023_01_20\EPICS
Running robocopy C:\Instrument\Apps\empty_dir_for_robocopy C:\Instrument\Apps\EPICS /PURGE /NJH /NJS /NP /NFL /NDL /NS /NC /R:1 /LOG:NUL ...
>

> Log File : \\.\NUL

Process failed with return code 2 (expected 0) and no output.
```
a return code of 2 is not a robocopy fail
```
0 No errors occurred, and no copying was done.
The source and destination directory trees are completely synchronized.

1 One or more files were copied successfully (that is, new files have arrived).

2 Some Extra files or directories were detected. No files were copied
Examine the output log for details.

4 Some Mismatched files or directories were detected.
Examine the output log. Housekeeping might be required.
```
an error code of 4 or more is an issue