GHA: add nightly-6.3-noble container image job

Now that 6.3 snapshots are available, we should cover this on CI.

Author: MaxDesiatov

.github/workflows/main.yml

@@ -137,6 +137,12 @@ jobs:
             wasi-swift-sdk-checksum: "b64dfad9e1c9ccdf06f35cf9b1a00317e000df0c0de0b3eb9f49d6db0fcba4d9"
             test-args: "--traits WasmDebuggingSupport --enable-code-coverage"
             build-dev-dashboard: true
+          - swift: "swiftlang/swift:nightly-6.3-noble"
+            development-toolchain-download: "https://download.swift.org/development/ubuntu2404/swift-DEVELOPMENT-SNAPSHOT-2025-10-02-a/swift-DEVELOPMENT-SNAPSHOT-2025-10-02-a-ubuntu24.04.tar.gz"
+            wasi-swift-sdk-download: "https://download.swift.org/development/wasm-sdk/swift-DEVELOPMENT-SNAPSHOT-2025-10-02-a/swift-DEVELOPMENT-SNAPSHOT-2025-10-02-a_wasm.artifactbundle.tar.gz"
+            wasi-swift-sdk-id: swift-DEVELOPMENT-SNAPSHOT-2025-10-02-a_wasm
+            wasi-swift-sdk-checksum: "b64dfad9e1c9ccdf06f35cf9b1a00317e000df0c0de0b3eb9f49d6db0fcba4d9"
+            test-args: "--traits WasmDebuggingSupport -Xswiftc -DWASMKIT_CI_TOOLCHAIN_NIGHTLY"
           - swift: "swiftlang/swift:nightly-main-noble"
             development-toolchain-download: "https://download.swift.org/development/ubuntu2404/swift-DEVELOPMENT-SNAPSHOT-2025-10-02-a/swift-DEVELOPMENT-SNAPSHOT-2025-10-02-a-ubuntu24.04.tar.gz"
             wasi-swift-sdk-download: "https://download.swift.org/development/wasm-sdk/swift-DEVELOPMENT-SNAPSHOT-2025-10-02-a/swift-DEVELOPMENT-SNAPSHOT-2025-10-02-a_wasm.artifactbundle.tar.gz"