feat(controller): use CRD status subresource

[jessesuen]

Resolves #771
Resolves #440

This change updates Argo Rollouts to enable the use of the CRD status subresource. The reason for doing so, is to allow the rollout controller to record the numeric metadata.generation into status.observedGeneration. This allows us to have a reliable indicator of a Rollout who's spec has (or has not yet) been observed by the controller (for example if the argo-rollouts controller was down). This is needed in situations when tooling needs to wait/block on a Rollout to become healthy, after making a spec change (e.g. Argo CD PostSync hook).

A huge consequence of this change, is that Rollouts can no longer update spec/metadata at the same time as status, since the latter requires a separate call to the rollout's /status endpoint. Most changes are in test expectations that currently expect updates on the resource and not resource/status.

The main code change is in rollout/sync.go, which splits the update of a rollout into two API calls, and promote.go which also needs to make two API calls during promotion.

This change also:

• removes the deprecated status.canary.stableRS field.
• reorganizes installation manifests so that there is only one role file to update

TODO:

• make sure this works with rollouts with an invalid spec. (e.g. can we still persist rollouts that have invalid specs)

[codecov-io]

Codecov Report

Merging #789 (df9f844) into master (ac74a9b) will decrease coverage by 0.07%.
The diff coverage is 76.31%.

@@            Coverage Diff             @@
##           master     #789      +/-   ##
==========================================
- Coverage   82.09%   82.01%   -0.08%     
==========================================
  Files          98       98              
  Lines        8523     8536      +13     
==========================================
+ Hits         6997     7001       +4     
- Misses       1085     1093       +8     
- Partials      441      442       +1     

Impacted Files	Coverage Δ
rollout/canary.go	78.90% <ø> (-0.33%)	⬇️
rollout/sync.go	70.51% <53.33%> (-1.57%)	⬇️
pkg/kubectl-argo-rollouts/cmd/promote/promote.go	95.45% <88.00%> (-4.55%)	⬇️
pkg/kubectl-argo-rollouts/info/rollout_info.go	78.94% <90.90%> (+1.92%)	⬆️
pkg/kubectl-argo-rollouts/cmd/abort/abort.go	100.00% <100.00%> (ø)
pkg/kubectl-argo-rollouts/cmd/retry/retry.go	100.00% <100.00%> (ø)
rollout/controller.go	71.50% <100.00%> (-0.97%)	⬇️
utils/conditions/conditions.go	78.72% <100.00%> (-0.66%)	⬇️

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[jessesuen]

This is the check that allows us to detect if rollout controller observed the new spec.

[khhirani]

LGTM