feat: 660 create an example to run damages and losses without input files

[ArdtK]

Issue addressed

Solves #660

Code of conduct

• I HAVE NOT added sensitive or compromised (test) data to the repository.
• I HAVE NOT added vulnerabilities to the repository.
• I HAVE discussed my solution with (other) members of the RA2CE team.

What has been done?

• Remove check in input files in init of Losses
• Move creation of analysis_collectiont to Ra2ceHandler.configure so the analyses can be manipulated between the init and the execute.
• Refactor readers (shouldn't be dataclasses - wrongly changed in feat: 595 adaptation run and combine losses and damages #616)
• Add an example notebook to prove running Damages and Losses without input files is possible.

Checklist

• Code is formatted using our custom black and isort definitions.
• Tests are either added or updated.
• Branch is up to date with master.
• Updated documentation if needed.

Additional Notes (optional)

Add any additional notes or information that may be helpful.