Make a documentdb kubectl plugin which handles failover

[xgerman]

We need a DocumentDB kubectl plugin (see https://github.com/cloudnative-pg/cloudnative-pg/blob/main/docs/src/kubectl-plugin.md for the CNPG one) which allows a Cx to promote a remote region and perform a site swap.

In particualr we would like to provide the equivalent of the following commands:

• https://github.com/cloudnative-pg/cloudnative-pg/blob/main/docs/src/kubectl-plugin.md#status
• https://github.com/cloudnative-pg/cloudnative-pg/blob/main/docs/src/kubectl-plugin.md#promote
• https://github.com/cloudnative-pg/cloudnative-pg/blob/main/docs/src/kubectl-plugin.md#logs - this will collect both pg and gw logs
• https://github.com/cloudnative-pg/cloudnative-pg/blob/main/docs/src/kubectl-plugin.md#launching-psql but we launch mongosh

we might add other commands as needed, e.g. I am very intrigued by simplifying multi-cloud./region deployments with an appropriate commands.

[alaye-ms]

Failover script: https://github.com/microsoft/documentdb-kubernetes-operator/blob/37f07240eb43368cc63bdf8446c0e15537c68ffa/scripts/aks-fleet-deployment/failover.sh

[guanzhousongmicrosoft]

https://krew.sigs.k8s.io/docs/developer-guide/distributing-with-krew/
https://krew.sigs.k8s.io/docs/developer-guide/release/new-plugin/

[alaye-ms]

Promote command is the highest priority