Add rollouts docs | SDCD-1289

[Aaron-9900]

What does this PR do? What is the motivation?

We now support Rollouts in Argo CD in CD Visibility

Merge instructions

Merge readiness:

• Ready for merge

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Additional notes

[github-actions]

Preview links (active after the build_preview check completes)

Modified Files

• https://docs-staging.datadoghq.com/aaron.hoffman/SDCD-1289_rollouts-documentation/continuous_delivery/deployments/argocd

[joepeeples]

A few small edit suggestions on the headings, otherwise LGTM!

[Aaron-9900]

/merge

[github-actions]

✅ Documentation Team Review

The documentation team has approved this pull request. Thank you for your contribution!

[dd-devflow]

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2025-05-28 12:47:46 UTC ℹ️ Start processing command /merge

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2025-05-28 12:47:56 UTC ℹ️ MergeQueue: waiting for PR to be ready

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2025-05-28 13:17:17 UTC ℹ️ MergeQueue: merge request added to the queue

The expected merge time in master is approximately 20m (p90).

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2025-05-28 13:17:29 UTC ❌ MergeQueue: This merge request is not mergeable, blocked by github

PR can't be merged according to github policy

[Aaron-9900]

/merge

[dd-devflow]

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2025-05-28 13:28:32 UTC ℹ️ Start processing command /merge

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2025-05-28 13:28:42 UTC ℹ️ MergeQueue: pull request added to the queue

The expected merge time in master is approximately 20m (p90).

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2025-05-28 13:28:58 UTC ❌ MergeQueue: This merge request is not mergeable, blocked by github

PR can't be merged according to github policy

[Aaron-9900]

/merge

[dd-devflow]

View all feedbacks in Devflow UI.

2025-05-28 13:39:24 UTC ℹ️ Start processing command /merge

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2025-05-28 13:39:39 UTC ℹ️ MergeQueue: pull request added to the queue

The expected merge time in master is approximately 20m (p90).

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2025-05-28 13:56:38 UTC ℹ️ MergeQueue: This merge request was merged