[JENKINS-72854] UX improvement: make pod templates readonly from UI for NonConfigurableKubernetesCloud

[Pldi23]

https://issues.jenkins.io/browse/JENKINS-72854

This issue is just a UX issue, backend do not save changes in pod templates for NonConfigurableKubernetesCloud (covered by NonConfigurableKubernetesCloudTest#configRoundTrip). But users are very confused as they may assume that changes should be saved.

Testing done

I tested manually by running NonConfigurableKubernetesCloudTest#configRoundTrip, I stopped the test in debug mode and verified that for NonConfigurableKubernetesCloud Pod templates can not be edited anymore from UI, user see the message This Pod template is associated with a non-configurable cloud setup. , "Save" button is not visible and "Delete Pod Template" on side panel is not visible.
For KubernetesCloud no changes on UX (it is still configrable).

Submitter checklist

• Make sure you are opening from a topic/feature/bugfix branch (right side) and not your main branch!
• Ensure that the pull request title represents the desired changelog entry
• Please describe what you did
• Link to relevant issues in GitHub or Jira
• Link to relevant pull requests, esp. upstream and downstream changes
• Ensure you have provided tests - that demonstrates feature works or fixes the issue

[Vlatombe]

There is a built-in mechanism in core to switch all controls to readonly

<j:set var="readOnlyMode" value="${instance.readonlyFromUi}"/>

[Pldi23]

There is a built-in mechanism in core to switch all controls to readonly

<j:set var="readOnlyMode" value="${instance.readonlyFromUi}"/>

@Vlatombe, Yeah, I tried to use it but enum dropdown is still active with it.

[jglick]

So fix enum.jelly in core?

[Pldi23]

So fix enum.jelly in core?

Ok, I agree it's more rational. Let's fix this in core.

[aneveux]

LGTM

[jglick]

Should this be closed in favor of jenkinsci/jenkins#9336?

[Pldi23]

Should this be closed in favor of jenkinsci/jenkins#9336?

No, we need both: current one and jenkinsci/jenkins#9336

[Pldi23]

@Vlatombe , @jglick If you are ok with this change could you please merge the PR (I don't have a required permissions).

[Vlatombe]

A few simplifications could be applied, but otherwise it looks good.

[Pldi23]

CI failure seems not related to the fix, might be a flake, @Vlatombe can you please retrigger the ci again as I don't have permissions?