Ensure we can run d2d mapping with a single source/from and multiple binaries/to

[pombredanne]

I would like to run a d2d for multiple binaries built from the same sources at once, e.g, a single source/from and multiple binaries/to. It could be we run one d2d for each binary?

See also:

• purl-next: Create CI/CD integration for PURL binary integrity validation #1774

[rejzzzz]

@pombredanne I tried shifting the one-to-one d2d mapping to one-to-many in #2014 , now instead to fetching a single binary, it now scans and fetches them all in a single run.

If there are any issues or edge cases that I missed please let me know! :)