License Scanning support for Swift
## Why are we doing this work
The Swift iOS framework is one of the prominent frameworks that is widely used for the development of iOS apps and Mac software. We will be adding support for license scanning for this framework so that users have access to license information in the dependency list furthering increasing coverage for license scanning based on customer demand.
Composition Analysis does not currently support [License Scanning](https://docs.gitlab.com/ee/user/compliance/license_scanning_of_cyclonedx_files/) for Swift dependencies. This causes confusion for users who need to understand the license associated with their Swift dependencies. Additionally, because we do not support Swift License Scanning we are not fully populating the Dependency List with Swift dependencies. Swift information is only propagated to the Vulnerability report.
### Proposal
* Add support for Swift license scanning, starting with https://swiftpackageindex.com/
* Follow on work for https://cocoapods.org/ support
### Implementation plan
WIP
To achieve this feature there will be two main parts:
- collecting swift package license information in the Package Metadata DB: https://gitlab.com/groups/gitlab-org/-/epics/13578+
- adjusting the rails application to ensure license scanning is correctly executed for swift components
NB: support for showing Swift components on the dependency list has already been done with: https://gitlab.com/gitlab-org/gitlab/-/issues/497347+
epic