fix(appset): normalize app spec before applying

[crenshaw-dev]

The AppSet controller can get into a state where it fights with the application controller.

For example, try an appset like this:

apiVersion: argoproj.io/v1alpha1
kind: ApplicationSet
metadata:
  name: test
spec:
  generators:
    - git:
        repoURL: https://github.com/test/test
        directories:
          - path: '*'
  template:
    metadata:
      name: '{{path}}-dev'
    spec:
      project: test
      source:
        repoURL: https://github.intuit.com/test/test
        targetRevision: release/dev
        path: '{{path}}'
        directory:
          jsonnet: {}
      destination:
        server: https://test
        namespace: '{{path}}'

Note that the application controller logs a bunch of stuff like this:

time="2023-07-12T16:28:29Z" level=info msg="Normalized app spec: {\"spec\":{\"source\":{\"directory\":null}}}"

It's fighting with the appset controller.

This PR normalizes before applying so there's nothing to fight about.

[codecov]

Codecov Report

Patch coverage: 100.00% and project coverage change: +0.02 🎉

Comparison is base (e2e0da7) 49.73% compared to head (2662557) 49.76%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #14481      +/-   ##
==========================================
+ Coverage   49.73%   49.76%   +0.02%     
==========================================
  Files         261      261              
  Lines       44705    44758      +53     
==========================================
+ Hits        22234    22272      +38     
- Misses      20284    20295      +11     
- Partials     2187     2191       +4     

Impacted Files	Coverage Δ
...cationset/controllers/applicationset_controller.go	62.64% <100.00%> (+0.10%)	⬆️
util/argo/argo.go	66.49% <100.00%> (+0.04%)	⬆️

... and 12 files with indirect coverage changes

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[ishitasequeira]

LGTM!!

[leoluz]

LGTM

[crenshaw-dev]

/cherry-pick release-2.8

[crenshaw-dev]

/cherry-pick release-2.7

[crenshaw-dev]

/cherry-pick release-2.6

[crenshaw-dev]

/cherry-pick release-2.5

[gcp-cherry-pick-bot]

Cherry-pick failed with Merge error b90f3bc774b05fc71a1f3cb8803eb66bfd20e5a7 into temp-cherry-pick-0fa364-release-2.6

[gcp-cherry-pick-bot]

Cherry-pick failed with Merge error b90f3bc774b05fc71a1f3cb8803eb66bfd20e5a7 into temp-cherry-pick-0fa364-release-2.5