Add progressbar to *.dmg extract process

[jan-vcapgemini]

As an IDEasy Mac user I expect that I can see how long the extraction of my *.dmg will take.
Currently most archives use a progressbar, but it seems like for *.dmg the progressbar is still missing.

[hohwille]

If you want to do this properly, you need to be aware of the progress of the extraction.
That would IMHO mean that you need to re-engineer the dmg file format and re-implement a Java processing functionality for it.

What we are doing is however two fold:

1. we mount the dmg
2. we copy the app from the mounted directory to our destination
3. we unmount the dmg

In step 2. we could simply use the copyWithProgressbar method instead of a regular copy method.