BridgeJS: support imports of JS `Promise` as `async` Swift #2523

Job	Run time
check-bridgejs-generated	1m 44s
Test BridgeJS against Swift versions (swift:6.2, 602.0.0)	1m 32s
Test BridgeJS against Swift versions (swift:6.1.2, 601.0.0)	1m 33s
build-examples	1m 43s
Build for native target (macos-15, Xcode_16.4)	1m 43s
prettier	9s
Build and Test (ubuntu-24.04, https://download.swift.org/swift-6.3-branch/ubuntu2404/swift-6.3-DE...	1m 44s
Build and Test (ubuntu-24.04, https://download.swift.org/development/ubuntu2404/swift-DEVELOPMENT...	1m 43s
Build and Test (ubuntu-22.04, https://download.swift.org/development/ubuntu2204/swift-DEVELOPMENT...	1m 43s
Build and Test (ubuntu-22.04, https://download.swift.org/swift-6.1-release/ubuntu2204/swift-6.1-R...	1m 44s
format	38s
deploy-examples	1s
	15m 57s

Provide feedback