Include phase strategy in plan status output

[yankcrime]

What this PR does / why we need it:
Phase strategy can be defined independently of that for a plan, so this commit includes this in the output so that the Operator behaviour is less confusing to the user.

The output of that command now looks like this:

Plan(s) for "zookeeper-instance" in namespace "default":
.
└── zookeeper-instance (Operator-Version: "zookeeper-0.2.0" Active-Plan: "deploy")
    ├── Plan deploy (serial strategy) [COMPLETE]
    │   ├── Phase zookeeper (parallel strategy) [COMPLETE]
    │   │   └── Step deploy [COMPLETE]
    │   └── Phase validation (serial strategy) [COMPLETE]
    │       ├── Step validation [COMPLETE]
    │       └── Step cleanup [COMPLETE]
    └── Plan validation (serial strategy) [NOT ACTIVE]
        └── Phase connection (serial strategy) [NOT ACTIVE]
            ├── Step connection [NOT ACTIVE]
            └── Step cleanup [NOT ACTIVE]

Fixes #1171

[alenkacz]

I have two small string nits, when we resolve that, this is good to be merged :)

[alenkacz]

this is not a very nice output :/ but I guess it's fine for now, I'll fix it once we merge it :)

This actually should never happen in real life... ? because the strategy should is mandatory in OV

[ANeumann82]

lgtm

[alenkacz]

Thank you! 👏