support updating primary labels/annotations after first time rollout

[kh34]

Implements #1032

[daviddelucca]

@kh34 does this issue solves copy Deployment annotations when a change is triggered? I am using v1.7.0 and noticed that annotations from primary Deployment are never updated after first rollout - If I change any annotation from my canary deployment, it nevers copied to primary one.

As example. I update my canary Deployment to something like:

apiVersion: apps/v1
kind: Deployment
metadata:
  annotations:
    hpa.autoscaling.banzaicloud.io/maxReplicas: "42"
    hpa.autoscaling.banzaicloud.io/minReplicas: "13"
...
spec:  
  template:
    metadata:
      annotations:        
        my.annotat: random

Added annotation my.annot and changed value from hpa.autoscaling.banzaicloud.io/maxReplicas. Flagger triggers a new deploy but hpa.autoscaling.banzaicloud.io/maxReplicas is never updated

apiVersion: apps/v1
kind: Deployment
metadata:
  annotations:
    hpa.autoscaling.banzaicloud.io/maxReplicas: "41"
    hpa.autoscaling.banzaicloud.io/minReplicas: "13"
...
spec:  
  template:
    metadata:
      annotations:
        my.annotat: random