Document GitOps RN 1.7.4 and 1.6.7

[Srivaralakshmi]

NOTE: From GitOps 1.7.0 onwards, we are documenting security issues in a new advisory format as part of errata updates.

Aligned team: Dev Tools

Purpose: To resolve the following issues:
https://issues.redhat.com/browse/RHDEVDOCS-5219
https://issues.redhat.com/browse/RHDEVDOCS-5218

OCP version this PR applies to: enterprise-4.10

Link to docs preview:

• Release notes for Red Hat OpenShift GitOps 1.7.4
• Release notes for Red Hat OpenShift GitOps 1.6.7

SME review: @reginapizza, @iam-veeramalla
QE review: @varshab1210
Peer-review:

[Srivaralakshmi]

SME review: @reginapizza, @iam-veeramalla
QE review: @varshab1210 , @ciiay

PTAL at the following PRs:

• Document GitOpsRN-1.7.4 #59014 - For 4.12
• Document GitOps RN 1.7.4 and 1.6.7 #59016 - For 4.11
• Document GitOps RN 1.7.4 and 1.6.7 #59018 - For 4.10
• Document GitOpsRN-1.6.7 #59019 - For 4.8
• Document GitOps Release Notes for 1.6.7 #59023 - For 4.9

The content for 1.7.4 and 1.6.7 is the same in the PRs. I have raised multiple PRs to avoid merge conflicts as the content supported is different for all OCP versions.

This will be useful during the PR merge. Thanks for your understanding and cooperation.

[rolfedh]

Peer review: LGTM

[varshab1210]

LGTM, thanks