Simplified deployment app (#691)

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### Proposed changes


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This is a new, simplified deployment app for PKO. It leverages the
kustomization that is maintained in `operator/config/default` to avoid
code duplication. It supports ONLY cluster-wide installation.

PKOv2 is designed to natively support multi-tenancy across namespaces
without needing to deploy separate instances of the operator into each
namespace. Looking back at
#328, we see
that the ability to deploy to multiple namespaces was added to address a
lack of isolation (see pulumi/home#2330). I
opened #690
to track adding support for single-namespace deployment.

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