[DOCS] Add 8.0.0 GA release notes (#83689)

Adds the 8.0.0 GA release notes. I created these by combining the 8.0.0-alpha1, -alpha2, -beta1, -rc1 and -rc2 releases notes.

Co-authored-by: Lisa Cawley <[email protected]>

Author: jrodewig

docs/reference/release-notes.asciidoc

@@ -6,6 +6,7 @@
 
 This section summarizes the changes in each release.
 
+* <<release-notes-8.0.0>>
 * <<release-notes-8.0.0-rc2>>
 * <<release-notes-8.0.0-rc1>>
 * <<release-notes-8.0.0-beta1>>
@@ -14,6 +15,7 @@ This section summarizes the changes in each release.
 
 --
 
+include::release-notes/8.0.0.asciidoc[]
 include::release-notes/8.0.0-rc2.asciidoc[]
 include::release-notes/8.0.0-rc1.asciidoc[]
 include::release-notes/8.0.0-beta1.asciidoc[]

docs/reference/release-notes/8.0.0-rc2.asciidoc

@@ -58,6 +58,9 @@ Machine Learning::
 Network::
 * Improve slow inbound handling to include response type {es-pull}80425[#80425]
 
+Packaging::
+* Convert repository plugins to modules {es-pull}81870[#81870] (issue: {es-issue}81652[#81652])
+
 Search::
 * Check nested fields earlier in kNN search {es-pull}80516[#80516] (issue: {es-issue}78473[#78473])