relax swift-syntax version constraint to allow 603 #2566

Job	Run time
Test BridgeJS against Swift versions (swift:6.1.2, 601.0.0)	2m 59s
Build and Test (ubuntu-24.04, https://download.swift.org/development/ubuntu2404/swift-DEVELOPMENT...	13m 6s
check-bridgejs-generated	2m 48s
Build and Test (ubuntu-22.04, https://download.swift.org/swift-6.1-release/ubuntu2204/swift-6.1-R...	14m 39s
Build for native target (macos-15, Xcode_16.4)	2m 49s
build-examples	19m 22s
Test BridgeJS against Swift versions (swift:6.3, 603.0.0)	3m 7s
Test BridgeJS against Swift versions (swift:6.2, 602.0.0)	2m 55s
Build and Test (ubuntu-24.04, https://download.swift.org/swift-6.3-branch/ubuntu2404/swift-6.3-DE...	13m 23s
Build and Test (ubuntu-22.04, https://download.swift.org/development/ubuntu2204/swift-DEVELOPMENT...	18m 14s
format	35s
prettier	9s
deploy-examples	0s
	1h 34m 6s

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