chore: Remove namespaced crds

[sfenman]

Fixes: #2359
Removed CRDs installation in the namespaced installation.
Also added a small README inside the manifests directory. Please let me know if it needs some more information in it.

Checklist:

• Either (a) I've created an enhancement proposal and discussed it with the community, (b) this is a bug fix, or (c) this is a chore.
• The title of the PR is (a) conventional with a list of types and scopes found here, (b) states what changed, and (c) suffixes the related issues number. E.g. "fix(controller): Updates such and such. Fixes #1234".
• I've signed my commits with DCO
• I have written unit and/or e2e tests for my change. PRs without these are unlikely to be merged.
• My builds are green. Try syncing with master if they are not.
• My organization is added to USERS.md.

[github-actions]

Go Published Test Results

1 834 tests   1 834 ✔️  2m 30s ⏱️
   105 suites         0 💤
       1 files           0 ❌

Results for commit 9ebd6b4.

♻️ This comment has been updated with latest results.

[codecov]

Codecov Report

Base: 81.70% // Head: 81.70% // No change to project coverage 👍

Coverage data is based on head (9ebd6b4) compared to base (3540032).
Patch has no changes to coverable lines.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #2516   +/-   ##
=======================================
  Coverage   81.70%   81.70%           
=======================================
  Files         126      126           
  Lines       19135    19135           
=======================================
  Hits        15634    15634           
  Misses       2708     2708           
  Partials      793      793           

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[github-actions]

E2E Tests Published Test Results

    2 files      2 suites   1h 40m 6s ⏱️
  95 tests   88 ✔️ 3 💤 4 ❌
194 runs  184 ✔️ 6 💤 4 ❌

For more details on these failures, see this check.

Results for commit 9ebd6b4.

♻️ This comment has been updated with latest results.

[zachaller]

Can we also update https://argo-rollouts.readthedocs.io/en/stable/installation/ to mention the two different installation methods?

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
No Duplication information

[sfenman]

Can we also update https://argo-rollouts.readthedocs.io/en/stable/installation/ to mention the two different installation methods?

Sure!