repod/action/task.py:
Change `CreateOutputPackageBasesTask` to optionally accept a dict, which
provides pkgbase names and their respective source URLs and will be used
in conjunction with any `OutputPackageBase` that is created and matches
the name of the pkgbase.
Change `ConsolidateOutputPackageBasesTask` to accept and optional
`UrlValidationSettings` object which is passed into a `SourceUrlCheck`
in its list of `Checks` in post_checks.

repod/action/workflow.py:
Change signatures of `add_packages_dryrun()` and `add_packages()` to
include the optional `pkgbase_urls` parameter for providing a dict of
pkgbase names and their respective source URLs.

repod/cli/cli.py:
Change `repod_file_repo_importpkg()` to call `add_packages_dryrun()` and
`add_packages()` providing the source URLs retrieved via the CLI.

tests/action/test_task.py:
Change tests for `CreateOutputPackageBasesTask` to include the changes to
the signature of the class.

tests/action/test_workflow.py:
Change tests for `add_packages_dryrun()` and `add_packages()` to also
provide the pkgbase_urls parameter.

tests/cli/test_cli.py:
Change tests for `repod_file_repo_importpkg()` to provide a the source
URLs provided via the CLI and expect the correct call to
`add_packages_dryrun()` and `add_packages()` (including pkgbase_urls).