Backport of docs: Consul v1.19 Release Notes into release/1.19.x

[hc-github-team-consul-core]

Backport

This PR is auto-generated from #21279 to be assessed for backporting due to the inclusion of the label backport/1.19.

🚨

Warning automatic cherry-pick of commits failed. If the first commit failed,
you will see a blank no-op commit below. If at least one commit succeeded, you
will see the cherry-picked commits up to, not including, the commit where
the merge conflict occurred.

The person who merged in the original PR is:
@boruszak
This person should manually cherry-pick the original PR into a new backport PR,
and close this one when the manual backport PR is merged in.

merge conflict error: unable to process merge commit: "73711c642d8a7d4d4c81e4d04f8ab244614cddb3", automatic backport requires rebase workflow

The below text is copied from the body of the original PR.

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Description

This PR adds the "Release Notes" page to the Consul documentation, describing the new and new and deprecated features for Consul v1.19.

Links

Deployment Preview: Consul v1.19 release notes

PR Checklist

• updated test coverage
• external facing docs updated
• appropriate backport labels added
• not a security concern

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Overview of commits

• 1c11448 - afb014a - 81a2da8 - 73711c6 - 2a468ec - 31b07bc

[github-team-consul-core-pr-approver]

Auto approved Consul Bot automated PR

[DanStough]

Backport assistant doesn't like the merge commits on the original PR. I'm going to re-open this with the squashed commit from main.