Use SwiftSyntax prebuilt action in CI #2721

Job	Run time
Test BridgeJS against Swift versions (swift:6.3, 603.0.2)	3m 8s
check-bridgejs-generated	3m 31s
build-examples	27m 24s
prettier	12s
Build for native target (macos-15, Xcode_26.0.1)	4m 4s
format	38s
Build and Test (ubuntu-24.04, https://download.swift.org/swift-6.3-branch/ubuntu2404/swift-6.3-DE...	13m 31s
Build and Test (ubuntu-24.04, https://download.swift.org/development/ubuntu2404/swift-DEVELOPMENT...	14m 36s
Build and Test (ubuntu-22.04, https://download.swift.org/development/ubuntu2204/swift-DEVELOPMENT...	19m 34s
deploy-examples	1s
	1h 26m 39s

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