[DOCS] Adds 8.4.0 release notes (#137621)

* [DOCS] Adds 8.4.0 release notes

* Updates the 8.4.0 release notes

* Adds 8.0.1 to 8.3.x links

* Adds 8.0.1 to 8.3.x content

* Fixes known issue broken link

* Final changes

* Update docs/CHANGELOG.asciidoc

Co-authored-by: Brandon Morelli <[email protected]>

* Update docs/CHANGELOG.asciidoc

Co-authored-by: Brandon Morelli <[email protected]>

* Update docs/CHANGELOG.asciidoc

Co-authored-by: Gidi Meir Morris <[email protected]>

* Update docs/CHANGELOG.asciidoc

Co-authored-by: Brandon Morelli <[email protected]>

* Update docs/CHANGELOG.asciidoc

Co-authored-by: Aleh Zasypkin <[email protected]>

* Update docs/CHANGELOG.asciidoc

Co-authored-by: Aleh Zasypkin <[email protected]>

* Update docs/CHANGELOG.asciidoc

Co-authored-by: Aleh Zasypkin <[email protected]>

* Update docs/CHANGELOG.asciidoc

Co-authored-by: Aleh Zasypkin <[email protected]>

* Review comments

* Updates description

* Review comments

* Review comment

Co-authored-by: Brandon Morelli <[email protected]>
Co-authored-by: Gidi Meir Morris <[email protected]>
Co-authored-by: Aleh Zasypkin <[email protected]>
Co-authored-by: Kibana Machine <[email protected]>