[Backport 8.14] [DOCS] Adds ES|QL and Pandas section to the Integrati…

…ons section (#2587)

* [DOCS] Adds ES|QL and Pandas section to the Integrations section.

* [DOCS] Fixes link.

* Apply suggestions from code review

Co-authored-by: Marci Windsheimer <333176+marciw@users.noreply.github.com>

* [DOCS] Moves ESQL-Pandas content to a new subpage.

* Update docs/guide/esql-pandas.asciidoc

Co-authored-by: marciw <333176+marciw@users.noreply.github.com>

* [DOCS] Addresses feedback.

* [DOCS] Adds section to Integrations that links to ES|QL subpage.

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Co-authored-by: Marci Windsheimer <333176+marciw@users.noreply.github.com>
(cherry picked from commit 41b091f)

Co-authored-by: István Zoltán Szabó <istvan.szabo@elastic.co>