Add wrote to device at speed MB/sec INFO log to `clone_persistent_storage`
Log the write speed in MB/sec to INFO from close_persistent_storage()
method of creatory.py.
- Reuses the same text and code from
extract_iso
- Depends on get_persistent_storage_size() function from tails_installer/utils.py
- Which in turn depends on a
luks2_header_size
key in tails_installer/config.py
Closes #20092 (closed)