Update eck and stack versions for 2.16 release. (#8252)

Signed-off-by: Michael Montgomery <[email protected]>

[2.15] Release notes and highlights for 2.15 (#8172) (#8191)

* added release notes and lightlights for 2.15

* change title updates

* remove known issues section

* removed leftover comment

* simplified release highlights

* release notes regenerated

* metricset pr description update

* release notes updates

* lines sorted

* release notes regenerated

(cherry picked from commit 31861ea)

Report memory usage by application (#7966) (#7967)

Changes the license reporting to not only show the total managed memory but also show a breakdown by application.

(cherry picked from commit 704f386)

update docs and release highlights to note logstash licensing (#7860) (…

…#7862)

* update docs and release highlights to note logstash licensing
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Co-authored-by: Michael Montgomery <[email protected]>
(cherry picked from commit 634ccd1)

Add release notes and highlights for 2.12.1 (#7667) (#7670)

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Co-authored-by: Michael Montgomery <[email protected]>

Update stack version in recipes (#7651) (#7652)

This updates elastic-agent/fleet-kubernetes-integration-nonroot.yaml and 
elastic-agent/ksm-sharding.yaml recipes which were not correctly updated
because they were created with a stack version different from the current
stack version and as we do a replacement of the current stack version to
update the versions in the recipes, these have not been replaced.

Release Notes + Highlights for 2.11.1 (#7510) (#7513)

* Release notes + Highlights for 2.11.1
* Also added known issues section in 2.11.0 highlights.
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Signed-off-by: Michael Montgomery <[email protected]>
(cherry picked from commit c95a6ca)

use cluster health endpoint instead of the health report endpoint for…

… scp e2e test (#7455) (#7463)

* avoid using health report endpoint for scp tests.

(cherry picked from commit 022881c)

Release notes and highlights for 2.10.0 release (#7264) (#7292)

Co-authored-by: Michael Montgomery <[email protected]>
(cherry picked from commit f8f3e60)

Co-authored-by: Istvan Nagy <[email protected]>

Remove experimental flag from stack config policies (#7044) (#7049)

(cherry picked from commit 4c50ca2)