Add notifications if a new profile version is available

[Skarlso]

Closes #1143

Testing

• Have your own Slack space and create a webhook URL outlined here: https://api.slack.com/messaging/webhooks
• Create a secret with the webhook URL

kubectl -n wego-system create secret generic slack-url \
--from-literal=address=https://hooks.slack.com/services/<token>

• Setup Slack notification for flux using the following notification provider:

apiVersion: notification.toolkit.fluxcd.io/v1beta1
kind: Provider
metadata:
  name: slack
  namespace: wego-system
spec:
  type: slack
  channel: general
  secretRef:
    name: slack-url

• Port forward all the things which is the notification-controller and the source-controller
• Start UI

./bin/gitops ui run --helm-repo-namespace wego-system --helm-repo-name podinfo --notification-controller-address http://localhost:8081

• Install main components

./gitops install --config-repo=ssh://git@github.com/Skarlso/gitops-training.git

• Create a profile app

./bin/gitops add app --name podinfo --url https://weaveworks.github.io/profiles-examples --config-repo ssh://git@github.com/Skarlso/gitops-training.git --chart podinfo  --deployment-type helm --auto-merge

• Update the profile yaml file to include a new version and update the code in your gitops repo
• Observe incoming messages to your slack channel

Interesting.. where is my message?

Update:

Works!

[aclevername]

couple nits- I'd wait for 2nd reviewer before merging 😄

[Himangini]

LGTM, 2 ques

• Did you find a place to document this ?

I'm looking for a place to document how to set up the alerting for the notification-controller to pick up and forward the notifications.

• Are you going to add testing steps ?

testing steps incoming

[Skarlso]

@Himangini Ah good questions!

testing steps

I'll add some, thanks

documentation

Nope, I have not. I'm hoping someone will point me to some docs I can update.

[Himangini]

LGTM 🎉
Re the documentation, I'll find out where's the best place to put it. Not a blocker for this PR :)