Add kubernetes version field

[RealHarshThakur]

Signed-off-by: Harsh Thakur harsh@civo.com

Description of your changes

Fixes https://github.com/crossplane-contrib/provider-civo/issues/22

I have:

• [x] Read and followed Crossplane's contribution process.
• [x] Run make reviewable test to ensure this PR is ready for review.

How has this code been tested

[RealHarshThakur]

Both the checks are passing for me locally. I do not know why the GH jobs are failing

[vishalanarase]

LGTM