Add flag ignore missing for set-function

[italvi]

It should be possible to add a flag, e.g. "--ignore-missing" for the "set"-command, s.t. if a file is provided no error message will be shown when a component in the file is not in the SBOM. This is useful for the use-case when a central database file is used for the command.

Currently an error is shown:
ERROR: Set not performed (at line 230) - The component "COORDINATES[MyExampleComponent@1.2.3]" was not found and could not be updated.

Desired behavior:
When provided the flag "--ignore-missing" the error should not happen.