added flux suspended resources retrieval plugin (derailed#1584)

* added flux suspended resources retrieval plugin

using this plugin, you can press Shift-S in "kustomizations" and "helmreleases" k9s sections to get a list of all suspended resources... a temporary patch till k9s will allow custom columns based on .spec in its views...

* Create rm-ns.yml

to test: create an "undeletable" namespace, with wrong finalizers:

```
apiVersion: v1
kind: Namespace
metadata:
  name: test
spec:
  finalizers:
    - foregroundDeletion
```

apply to cluster: `kubectl create -f test.yaml`

go in NS view in k9s, then select the test NS and press CTRL-D to delete it... it will stay in terminating state, because of the finalizers... now press "n", and confirm, to remove the finalizers... the NS should now be gone...

do NOT run on the "all+" ns, it will crash k9s...

plugins/get_suspended.yml

@@ -0,0 +1,23 @@
+# credits: https://github.com/fluxcd/flux2/discussions/2494
+  get-suspended-helmreleases:
+    shortCut: Shift-S
+    confirm: false
+    description: Suspended Helm Releases
+    scopes:
+      - helmrelease
+    command: sh
+    background: false
+    args:
+      - -c
+      - "kubectl get --all-namespaces helmreleases.helm.toolkit.fluxcd.io -o json | jq -r '.items[] | select(.spec.suspend==true) | [.metadata.namespace,.metadata.name,.spec.suspend] | @tsv' | less"
+  get-suspended-kustomizations:
+    shortCut: Shift-S
+    confirm: false
+    description: Suspended Kustomizations
+    scopes:
+      - kustomizations
+    command: sh
+    background: false
+    args:
+      - -c
+      - "kubectl get --all-namespaces kustomizations.kustomize.toolkit.fluxcd.io -o json | jq -r '.items[] | select(.spec.suspend==true) | [.metadata.name,.spec.suspend] | @tsv' | less"

plugins/rm-ns.yml

@@ -0,0 +1,13 @@
+plugin:
+  # remove finalizers from a stuck namespace
+  rm-ns:
+    shortCut: n
+    confirm: true
+    description: Remove NS Finalizers
+    scopes:
+    - namespace
+    command: sh
+    background: false
+    args:
+    - -c
+    - "kubectl get namespace $NAME -o json | jq '.spec.finalizers=[]' | kubectl replace --raw /api/v1/namespaces/$NAME/finalize -f - > /dev/null"