fix(service): better handling of script names

[imobachgs]

Problem

There are a few problems when importing an AutoYaST script:

• Agama uses file_name instead of filename.
• If file_name is missing, it does not propose another name, generating an invalid profile.

Solution

Fix both problems by:

• Using the right attribute name (filename instead of file_name).
• Falling back to the basename from the location. If no location is given, propose script-X
  where X is a number.

Testing

• Added a new unit test
• Tested manually

[jreidinger]

@imobachgs we really mess up with our amount of delayed PR as exactly this fixes I have in my PR #1946

[jreidinger]

to be precise I solve it slightly differently, but I have those fixes and also test for it :)

[imobachgs]

to be precise I solve it slightly differently, but I have those fixes and also test for it :)

Yes, I saw it later. Well, the main difference is that in this case I am trying to infer the name of the script from the URL if it is not given. But feel free to close it if you prefer the other way.

The only think I do not like about your PR is the "anonymous-" prefix. I would rather prefer something like "script-" or similar.

[imobachgs]

Well, to reduce the duplication, I am closing this PR. I will review yours.

[jreidinger]

thanks, change of fallback name is really trivial in mine...lets discuss it there.