BridgeJS: Fix memory management of SwiftHeapObject #2379

Job	Run time
prettier	7s
format	25s
Test BridgeJS against Swift versions (swift:6.1.2, 601.0.0)	22s
Build and Test (ubuntu-24.04, https://download.swift.org/swift-6.3-branch/ubuntu2404/swift-6.3-DE...	37s
Build and Test (ubuntu-24.04, https://download.swift.org/development/ubuntu2404/swift-DEVELOPMENT...	37s
Build and Test (ubuntu-22.04, https://download.swift.org/swift-6.1-release/ubuntu2204/swift-6.1-R...	25s
check-bridgejs-generated	37s
Build and Test (ubuntu-22.04, https://download.swift.org/development/ubuntu2204/swift-DEVELOPMENT...	37s
Test BridgeJS against Swift versions (swift:6.2, 602.0.0)	25s
build-examples	36s
Build for native target (macos-15, Xcode_16.4)	39s
deploy-examples	1s
	5m 28s

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