Increase self hosted coverage

[bkhouri]

Description

In order to gain confidence in our changes, the swiftpm project should have self hosted pipelines for the all platforms that support Swift. possibly the following

• Ubuntu 20.04
• Ubuntu 22.04
• Ubuntu 24.04
• Amazon Linux 2
• Universal Base Image 9
• Debian 12
• Windows 10
• Windows 11 (?)
• macOS

Swift PM does not have any architecture-specific code (I don't think), so x86_64 is sufficient

Acceptance Criteria

• new pipelines are non-gating until their behaviour is confirmed, after which, we mark them gating
• The pipelines (new and existing) should use a Swift Toolchain version specified by the .swift-versionfound in the repository. If this file does not exists, use the latest released Swift Toolchain.

[jakepetroules]

Once @shahmishal activates GitHub Actions for SwiftPM, that should get us pretty much all of this.

Swift PM does not have any architecture-specific code (I don't think), so x86_64 is sufficient

There are definitely architecture-specific paths at runtime; we'd benefit from arm64 jobs. (Swift Build, too)

The pipelines (new and existing) should use a Swift Toolchain version specified by the .swift-versionfound in the repository. If this file does not exists, use the latest released Swift Toolchain.

With GitHub Actions we'll be able test against multiple Swift versions concurrently. Testing against a single one specified by .swift-version is too limiting, and we MUST also be testing against nightlies.

[bkhouri]

Yes, GitHub Actions will open a whole new world. This issues description assumes we are using the current Jenkins build infrastructure.