flush observability on error (#5595)
flush observability on error (#5595)

motivation: follow up on previsou changes to queue observability messages

changes: catch error an flush on those cases as well
apple/swift-package-manager,abertelrud/swift-package-manager,apple/swift-package-manager,apple/swift-package-manager,abertelrud/swift-package-manager,apple/swift-package-manager,apple/swift-package-manager,abertelrud/swift-package-manager,abertelrud/swift-package-manager,abertelrud/swift-package-manager