chore: HA manifests: remove hardcoded *-processors overriding any other settings

[nazarewk]

Checklist:

• Either (a) I've created an enhancement proposal and discussed it with the community, (b) this is a bug fix, or (c) this does not need to be in the release notes.
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Overview

This PR is a 4 years old zombie code removal

At time the change was introduced (and not revised later on) there were no CM mappings and no envvars handling in the code itself. Those hardcoded values prevent any kind of modifications anywhere else (they have highest priority) as described in slack thread and #2720

Original discussion: https://cloud-native.slack.com/archives/C01TSERG0KZ/p1661436953901989
fixes #2720

[codecov]

Codecov Report

Merging #10458 (a4bbf8d) into master (a23bfc3) will not change coverage.
The diff coverage is 53.94%.

@@           Coverage Diff           @@
##           master   #10458   +/-   ##
=======================================
  Coverage   45.76%   45.76%           
=======================================
  Files         233      234    +1     
  Lines       28401    28460   +59     
=======================================
+ Hits        12998    13025   +27     
- Misses      13629    13658   +29     
- Partials     1774     1777    +3     

Impacted Files	Coverage Δ
cmd/argocd/commands/admin/notifications.go	0.00% <0.00%> (ø)
pkg/apiclient/apiclient.go	0.94% <0.00%> (-0.03%)	⬇️
server/notification/notification.go	56.00% <56.00%> (ø)
server/server.go	52.49% <100.00%> (+0.95%)	⬆️

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[jannfis]

Thanks @nazarewk, this change absolutely makes sense.

Please run make manifests (or make manifests-local, considering you have Kustomize and Helm installed in similar versions to what's expected by Argo CD) to satisfy the codegen check.

[jannfis]

LGTM. Thanks!