BridgeJS: Fix reject path of zero-parameter async throwing exports #2683

Job	Run time
Build for native target (macos-15, Xcode_16.4)	2m 34s
Test BridgeJS against Swift versions (swift:6.2, 602.0.0)	3m 18s
format	31s
Test BridgeJS against Swift versions (swift:6.3, 603.0.0)	3m 0s
Build and Test (ubuntu-22.04, https://download.swift.org/development/ubuntu2204/swift-DEVELOPMENT...	18m 38s
build-examples	20m 23s
Build and Test (ubuntu-24.04, https://download.swift.org/swift-6.3-branch/ubuntu2404/swift-6.3-DE...	13m 12s
Test BridgeJS against Swift versions (swift:6.1.2, 601.0.0)	3m 8s
Build and Test (ubuntu-24.04, https://download.swift.org/development/ubuntu2404/swift-DEVELOPMENT...	14m 15s
Build and Test (ubuntu-22.04, https://download.swift.org/swift-6.1-release/ubuntu2204/swift-6.1-R...	13m 59s
check-bridgejs-generated	3m 0s
prettier	15s
deploy-examples	-1s
	1h 36m 12s

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