fix: configure kubernetes synchronizer to watch All or specifiec name…

[kamiiiel]

Description

At the moment Kubernetes synchroniser is watching all namespaces and there is no way to configure it. This PR will make the synchronizer to only watch to the current namespace that the Gateway is running inside it by default but the user can change this behaviour by setting the 'namespace' attribute.

🚀 CI was able to deploy the build of this PR, so you can now try it directly here
Notes: The deployed app is linked to the management API of APIM master. (Same login and password as APIM master)

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📚  View the storybook of this branch here

[ThibaudAV]

I wonder if using labels would not be more flexible 🤔 And more in the ways of doing k8s 🤷‍♂️
but both would be even better 😁 WDYT @sebdevaux

What do you think about adding some tests on it ?

[ThibaudAV]

There will surely be things to change here too.
because actually CRD are on default ns and apim on apim-dev ns of k3d

[kamiiiel]

@brasseld , @ThibaudAV can you please approve this PR if nothing else needs to be modified.

[brasseld]

@kamiiiel Do we agree that if no namespace is configured, then we are watching all namespaces ?

[kamiiiel]

@kamiiiel Do we agree that if no namespace is configured, then we are watching all namespaces ?

If we don't provide any namespace, we only listen to the current namespace that the gateway is running inside it.
Btw, we will get errors if want to watch different namespaces but we don't use ClusterRole for our service account.