feat: impl'd describe for pods (#553)

[adietish]

partially fixes #553: it only provides "describe" for pods, no other resource kind is supported. Support for these is filed at #782

How to test this:

This implementation should provide the same output as kubectl describe pod <name>.

Steps:

1. EXEC: copy & paste the following into an editor in IJ, naming the file "describe-test.yml":
   https://gist.github.com/adietish/b9bde277776f657af7d76515effa1882#file-describe-test-yml. Then push the editor to the cluster.
   (alternatively you can also use kubectl with the file: kubectl apply -f describe-test.yml)
2. ASSERT: a Pod describe-test is created and show up in the resource tree
3. EXEC: pick "Describe" in the context menu to the pod describe-test ([cluster] > Workloads > Pods > describe-test)
4. ASSERT: An editor is opened describing the pod. The title of the editor is "Describe Pod describe-test".
5. EXEC: run kubectl describe pod describe-test and compare the output with the content of the editor

Comparing the outputs:
You can use a diff or https://www.diffchecker.com/text-compare/ which helps a lot.
There are limitations that were not implemented yet (ex. the list of events that kubectl is printing in the end of the output):

• Describe: describe events for a given pod #778
• Describe: Impl resource resolution for env vars #774
• Describe: display CSI Volume source attributes #776
• Describe: describe QOS for pods which dont have a QosClass property in status #777
• Describe: support other resources than pod #782

The following examples show equivalence in intellij-kubernetes and kubectl. The differences are mainly in formatting, cause by the fact the intellij-kubernetes is producing YAML whereas kubectl is simply printing text.

Examples:

• kubectl

Labels:     luke=skywalker
            princess=leia

• intellij-kubernetes (creates a yaml mapping, <key>:<value> instead of <key>=<value>)

Labels:
  luke: skywalker
  princess: leia

• kubectl

Medium:

• intellij-kubernetes (prints <none> instead of ``)

Medium: <none>

• kubectl

Readiness Gates:
  Type                     Status
  www.example.com/gate-1   <none>
  ContainersReady          <none>

• intellij-kubernetes (skips heading: "Type Status")

  www.example.com/gate-1: <none>
  ContainersReady: <none>

• kubectl

Tolerations:    gpu=true:NoSchedule
                node.kubernetes.io/not-ready:NoExecute for 3600s
                node.kubernetes.io/unreachable:NoExecute op=Exists for 3600s
                project=system:NoSchedule

• intellij-kuberetes (creates a yaml sequence, each element starts with -):

Tolerations:
- gpu=true:NoSchedule
- project=system:NoSchedule
- node.kubernetes.io/unreachable:NoExecute op=Exists for 3600s
- node.kubernetes.io/not-ready:NoExecute for 3600s

• kubectl

Environment:
      MY_POD_NAME:             describe-test (v1:metadata.name)

• intellij-kubernetes (does not resolve expression v1:metadata.name to the value describe-test. It only prints the expression (v1:metadata-name). Known limitation, filed to Describe: Impl resource resolution for env vars #774)

Environment:
    MY_POD_NAME: (v1:metadata.name)

[adietish]

@sbouchet I also changed Command to better match kubectl:

• kubectl:

   Command:
      /kuberos
      https://accounts.google.com
      REDACTED.apps.googleusercontent.com
      /cfg/secret
      /cfg/template

• intellij-kubernetes:

   Command: |-
      /kuberos
      https://accounts.google.com
      REDACTED.apps.googleusercontent.com
      /cfg/secret
      /cfg/template

[adietish]

@sbouchet please re-review, thanks!

[sbouchet]

nitpicking copyrights. LGTM !

[sonarcloud]

Quality Gate passed

Issues
0 New issues
2 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud