OC cli sub-service-commands fail to execute

[fschade]

Describe the bug

as mentioned here, running sub services from within the oc binary fails with:

panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x2 addr=0x0 pc=0x10181afc4]

goroutine 1 [running]:
github.com/opencloud-eu/opencloud/services/antivirus/pkg/command.Server.func2(0x1400057a780)
        /Users/fschade/Developer/fschade/opencloud/services/antivirus/pkg/command/server.go:45 +0x1c4
github.com/urfave/cli/v2.(*Command).Run(0x14001421080, 0x1400057a780, {0x14000af2590, 0x1, 0x1})
        /Users/fschade/go/pkg/mod/github.com/urfave/cli/v2@v2.27.7/command.go:276 +0x580
github.com/urfave/cli/v2.(*Command).Run(0x140014214a0, 0x1400057a6c0, {0x1400056ce20, 0x2, 0x2})
        /Users/fschade/go/pkg/mod/github.com/urfave/cli/v2@v2.27.7/command.go:269 +0x774
github.com/urfave/cli/v2.(*Command).Run(0x140010ceb00, 0x1400057a600, {0x14000124990, 0x3, 0x3})
        /Users/fschade/go/pkg/mod/github.com/urfave/cli/v2@v2.27.7/command.go:269 +0x774
github.com/urfave/cli/v2.(*App).RunContext(0x14000f90a00, {0x104a664a8, 0x140011d4cc0}, {0x14000124990, 0x3, 0x3})
        /Users/fschade/go/pkg/mod/github.com/urfave/cli/v2@v2.27.7/app.go:333 +0x4c8
github.com/opencloud-eu/opencloud/opencloud/pkg/command.Execute()
        /Users/fschade/Developer/fschade/opencloud/opencloud/pkg/command/root.go:32 +0x1b4
main.main()
        /Users/fschade/Developer/fschade/opencloud/opencloud/cmd/opencloud/main.go:11 +0x1c
exit status 2

Steps to reproduce

• go run opencloud/cmd/opencloud/main.go antivirus server
• go run opencloud/cmd/opencloud/main.go ... server

[fschade]

regression, will be fixed after our new cli is merged here: #1954