Make Swift SDK host platform independent

[kateinoigakukun]

We currently build Swift SDK for each host platform (macOS x86_64, macOS arm64, Ubuntu, etc...). But in theory, we don't need those variants, we just need a host platform independent single SDK

We need the following changes to make it possible.

• https://github.com/apple/swift/pull/72212
• https://github.com/apple/swift/pull/70715

[kateinoigakukun]

https://github.com/swiftwasm/swiftwasm-build/pull/251 made the SDKs platform independent. We still need to adjust distribution script to release it as: swift-wasm-DEVELOPMENT-SNAPSHOT-2024-03-29-a.artifactbundle.zip instead of swift-wasm-DEVELOPMENT-SNAPSHOT-2024-03-29-a-ubuntu18.04_x86_64.artifactbundle.zip

[kateinoigakukun]

We now have swift-wasm-DEVELOPMENT-SNAPSHOT-2024-04-14-a-wasm32-unknown-wasi.artifactbundle.zip from yesterday.

See https://github.com/swiftwasm/swift/releases/tag/swift-wasm-DEVELOPMENT-SNAPSHOT-2024-04-14-a