feat: Add tests for app cmd

[pasha-codefresh]

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[terrytangyuan]

Great tests.

[codecov]

Codecov Report

Merging #8872 (abaf320) into master (a6c664b) will increase coverage by 0.05%.
The diff coverage is 16.21%.

@@            Coverage Diff             @@
##           master    #8872      +/-   ##
==========================================
+ Coverage   42.87%   42.93%   +0.05%     
==========================================
  Files         186      186              
  Lines       23335    23359      +24     
==========================================
+ Hits        10006    10029      +23     
+ Misses      11898    11891       -7     
- Partials     1431     1439       +8     

Impacted Files	Coverage Δ
cmd/argocd/commands/app.go	2.12% <0.00%> (+1.19%)	⬆️
cmd/argocd/commands/app_actions.go	0.00% <0.00%> (ø)
controller/cache/cache.go	20.76% <0.00%> (ø)
pkg/apis/application/v1alpha1/app_project_types.go	51.83% <0.00%> (-0.28%)	⬇️
server/application/application.go	31.37% <7.14%> (-0.19%)	⬇️
controller/appcontroller.go	51.61% <38.46%> (-0.21%)	⬇️
util/settings/settings.go	48.10% <0.00%> (ø)

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[crenshaw-dev]

LGTM!