panic if containers contain an aci that does not exists in the repository

[n0rad]

[signal 0xb code=0x1 addr=0x0 pc=0x89d5b]

goroutine 1 [running]:
panic(0x76b980, 0xc8200101e0)
        /usr/lib/go/src/runtime/panic.go:481 +0x3e6
github.com/blablacar/ggn/work.(*Service).PrepareAcis(0xc820438900, 0x0, 0x0, 0x0, 0x0, 0x0)
        /home/n0rad/Work/go/src/github.com/blablacar/ggn/work/service-generate.go:223 +0xe2b
github.com/blablacar/ggn/work.(*Unit).Generate(0xc82022f200, 0xc8201bfce0, 0x0, 0x0)
        /home/n0rad/Work/go/src/github.com/blablacar/ggn/work/unit-generate.go:26 +0x11e
github.com/blablacar/ggn/work.(*Service).Generate(0xc820438900, 0x0, 0x0)
        /home/n0rad/Work/go/src/github.com/blablacar/ggn/work/service-generate.go:46 +0x3b4
github.com/blablacar/ggn/work.(*Service).Update(0xc820438900, 0x0, 0x0)
        /home/n0rad/Work/go/src/github.com/blablacar/ggn/work/service-update.go:16 +0x31
github.com/blablacar/ggn/commands.prepareServiceCommands.func7(0xc82034b380, 0xc8201bfc80, 0x0, 0x3)
        /home/n0rad/Work/go/src/github.com/blablacar/ggn/commands/prepare-service.go:89 +0x20
github.com/blablacar/ggn/vendor/github.com/spf13/cobra.(*Command).execute(0xc82034b380, 0xc8201bfb00, 0x3, 0x3, 0x0, 0x0)
        /home/n0rad/Work/go/src/github.com/blablacar/ggn/vendor/github.com/spf13/cobra/command.go:477 +0x3f4
github.com/blablacar/ggn/vendor/github.com/spf13/cobra.(*Command).Execute(0xc82018e4e0, 0x0, 0x0)
        /home/n0rad/Work/go/src/github.com/blablacar/ggn/vendor/github.com/spf13/cobra/command.go:551 +0x46a
github.com/blablacar/ggn/commands.loadEnvCommandsReturnNewRoot.func1(0xc8202e8b60, 0xced828, 0x0, 0x0)
        /home/n0rad/Work/go/src/github.com/blablacar/ggn/commands/prepare.go:28 +0x10b
github.com/blablacar/ggn/vendor/github.com/spf13/cobra.(*Command).execute(0xc8202e8b60, 0xced828, 0x0, 0x0, 0x0, 0x0)
        /home/n0rad/Work/go/src/github.com/blablacar/ggn/vendor/github.com/spf13/cobra/command.go:477 +0x3f4
github.com/blablacar/ggn/vendor/github.com/spf13/cobra.(*Command).Execute(0xc82018e340, 0x0, 0x0)
        /home/n0rad/Work/go/src/github.com/blablacar/ggn/vendor/github.com/spf13/cobra/command.go:551 +0x46a
github.com/blablacar/ggn/commands.Execute(0x0, 0x0, 0xa07558, 0xa, 0xa09170, 0x17)
        /home/n0rad/Work/go/src/github.com/blablacar/ggn/commands/ggn.go:53 +0x6b9
main.main()
        /home/n0rad/Work/go/src/github.com/blablacar/ggn/main.go:16 +0xce