Fix panic on first HA controller startup

[plorenz]

panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x2 addr=0x20 pc=0x103426680]

goroutine 1 [running]:
github.com/openziti/ziti/controller.(*Controller).GetApiAddresses.func1()
        /Users/eugene/work/openziti/ziti/controller/controller.go:604 +0x30
sync.(*Once).doSlow(0x18?, 0x0?)
        /opt/homebrew/Cellar/go/1.22.1/libexec/src/sync/once.go:74 +0x100
sync.(*Once).Do(...)
        /opt/homebrew/Cellar/go/1.22.1/libexec/src/sync/once.go:65
github.com/openziti/ziti/controller.(*Controller).GetApiAddresses(0x14000d20c60)
        /Users/eugene/work/openziti/ziti/controller/controller.go:603 +0x50
github.com/openziti/ziti/controller.(*Controller).GetHelloHeaderProviders.func1(0x14000ebac00)
        /Users/eugene/work/openziti/ziti/controller/controller.go:627 +0x28
github.com/openziti/ziti/controller/raft/mesh.HeaderProviderFunc.Apply(0x104905d00?, 0x14000ebac00?)
        /Users/eugene/work/openziti/ziti/controller/raft/mesh/mesh.go:599 +0x28
github.com/openziti/ziti/controller/raft/mesh.(*impl).GetPeerInfo(0x14000c64540, {0x14000981e00, 0x12}, 0x4?)
        /Users/eugene/work/openziti/ziti/controller/raft/mesh/mesh.go:351 +0x3d0
github.com/openziti/ziti/controller/raft.(*Controller).addConfiguredBootstrapMembers(0x14000c626c0)
        /Users/eugene/work/openziti/ziti/controller/raft/raft.go:691 +0x98
github.com/openziti/ziti/controller/raft.(*Controller).Bootstrap(0x14000c626c0)
        /Users/eugene/work/openziti/ziti/controller/raft/raft.go:655 +0x90
github.com/openziti/ziti/controller.NewController(0x14000c385a0, {0x104dd4528, 0x106773dc8})
        /Users/eugene/work/openziti/ziti/controller/controller.go:234 +0x4d8
github.com/openziti/ziti/ziti/controller.run(0x14000c29a00?, {0x14000b8be30, 0x1, 0x103ec7d48?})
        /Users/eugene/work/openziti/ziti/ziti/controller/run.go:63 +0x554
github.com/spf13/cobra.(*Command).execute(0x14000acf208, {0x14000b8be00, 0x1, 0x1})
        /Users/eugene/go/pkg/mod/github.com/spf13/cobra@v1.8.0/command.go:987 +0x828
github.com/spf13/cobra.(*Command).ExecuteC(0x1065befc0)
        /Users/eugene/go/pkg/mod/github.com/spf13/cobra@v1.8.0/command.go:1115 +0x344
github.com/spf13/cobra.(*Command).Execute(...)
        /Users/eugene/go/pkg/mod/github.com/spf13/cobra@v1.8.0/command.go:1039
github.com/openziti/ziti/ziti/cmd.Execute()
        /Users/eugene/work/openziti/ziti/ziti/cmd/cmd.go:82 +0x24
main.main()
        /Users/eugene/work/openziti/ziti/ziti/main.go:51 +0x1c