Heterogeneous architecture clusters - Console backend changes

This enhancement Introduces support for provisioning and upgrading heterogenous architecture clusters in phases.

We need to scan through the compute nodes and build a set of supported architectures from those. Each node on the cluster has a label for architecture: e.g. kubernetes.io/arch=arm64, kubernetes.io/arch=amd64 etc. Based on the set of supported architectures console will need to surface only those operators in the Operator Hub, which are supported on our Nodes.

AC: 

1. Implement logic in the console-operator that will scan though all the nodes and build a set of all the architecture types that the cluster nodes run on and pass it to the console-config.yaml
2. Add unit and e2e test cases in the console-operator repository.

@jpoulin is good to ask about heterogeneous clusters.