feat: Istio Subset-Level TrafficRouting with experiment step

[khhirani]

As described in comments of #1059

[codecov]

Codecov Report

Merging #1602 (b3913c9) into master (9d2ccb9) will increase coverage by 0.18%.
The diff coverage is 77.50%.

@@            Coverage Diff             @@
##           master    #1602      +/-   ##
==========================================
+ Coverage   81.77%   81.96%   +0.18%     
==========================================
  Files         113      115       +2     
  Lines       15573    15885     +312     
==========================================
+ Hits        12735    13020     +285     
- Misses       2176     2196      +20     
- Partials      662      669       +7     

Impacted Files	Coverage Δ
rollout/trafficrouting/alb/alb.go	84.00% <0.00%> (ø)
rollout/trafficrouting/nginx/nginx.go	80.19% <0.00%> (ø)
rollout/trafficrouting/smi/smi.go	94.90% <0.00%> (ø)
rollout/trafficrouting.go	68.78% <66.66%> (+0.16%)	⬆️
rollout/trafficrouting/istio/istio.go	81.16% <88.88%> (+0.22%)	⬆️
rollout/trafficrouting/ambassador/ambassador.go	83.15% <100.00%> (ø)
controller/metrics/metrics.go	100.00% <0.00%> (ø)
controller/controller.go	89.45% <0.00%> (ø)
controller/healthz.go	100.00% <0.00%> (ø)
... and 2 more

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[harikrongali]

@khhirani please resolve merge conflicts..will review after resolving merge conflicts

[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
3 Code Smells

No Coverage information
7.7% Duplication

[perenesenko]

The code looks good to me.
The question I have are we going to show the experiment traffic somehow on a argo-rollout console view?

Name:            rollouts-demo
Namespace:       default
Status:          ॥ Paused
Message:         CanaryPauseStep
Strategy:        Canary
  Step:          3/4
  SetWeight:     20
  ActualWeight:  20
Images:          argoproj/rollouts-demo:orange (canary)
                 argoproj/rollouts-demo:red (stable)

@khhirani @harikrongali
We do show the canary weight 20 there but are we going to display the experiment also?

[harikrongali]

@perenesenko we have an enhancement reported for that #1463

[alexmt]

LGTM