feat: add support to backup applicationsets

[chetan-rns]

Currently, users can backup Argo CD data using argocd-util export command. This commit adds support to export and import ApplicationSets along with other Argo CD resources.

Closes: #5240

Example:
The following command will also export ApplicationSets if they're present.

argocd-util export -o backup.yaml

Signed-off-by: Chetan Banavikalmutt chetanrns1997@gmail.com

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[codecov]

Codecov Report

Merging #6095 (6d02b06) into master (bfd0b15) will decrease coverage by 0.06%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##           master    #6095      +/-   ##
==========================================
- Coverage   40.93%   40.87%   -0.07%     
==========================================
  Files         147      147              
  Lines       19729    19848     +119     
==========================================
+ Hits         8077     8113      +36     
- Misses      10541    10614      +73     
- Partials     1111     1121      +10     

Impacted Files	Coverage Δ
cmd/argocd-util/commands/argocd_util.go	14.51% <0.00%> (-0.12%)	⬇️
cmd/argocd-util/commands/backup.go	0.00% <0.00%> (ø)
server/application/application.go	30.91% <0.00%> (+0.18%)	⬆️

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[chetan-rns]

Wanted to add an e2e test for this. But the test server doesn't add appset CRD. Any pointers on how to overcome this would be helpful.

[jannfis]

Wanted to add an e2e test for this. But the test server doesn't add appset CRD. Any pointers on how to overcome this would be helpful.

Hey @chetan-rns, you could add the applicationset CRD to https://github.com/argoproj/argo-cd/blob/master/test/manifests/base/kustomization.yaml - this is what gets installed to the K8s cluster used for end-to-end tests here

Maybe this could even be included as a remote resource from the applicationset repo.

[chetan-rns]

Thanks @jannfis 👍

[jannfis]

LGTM, thanks @chetan-rns

As it turns out, argocd-util is not (yet) included in e2e tests at all. From my PoV, e2e tests are not a requirement for this PR.