Docs update 23.1 (#347)

* release notes for 23.1

* updated version to 23.1

* removed note

* revert to nightly version

* correct version for helm install

* fixed uninstall release version

* fixed wrong operator name

* Update modules/ROOT/pages/release_notes.adoc

Co-authored-by: Razvan-Daniel Mihai <84674+razvan@users.noreply.github.com>

* Update modules/ROOT/pages/release_notes.adoc

Co-authored-by: Razvan-Daniel Mihai <84674+razvan@users.noreply.github.com>

* Update modules/ROOT/pages/release_notes.adoc

Co-authored-by: Razvan-Daniel Mihai <84674+razvan@users.noreply.github.com>

* added mention of new demo/stack/tutorial

* replace links with xrefs

Co-authored-by: Felix Hennig <fhennig@users.noreply.github.com>
Co-authored-by: Razvan-Daniel Mihai <84674+razvan@users.noreply.github.com>

Author: 3 people

modules/ROOT/pages/index.adoc

@@ -4,28 +4,6 @@
 Welcome to Stackable!
 This documentation gives you an overview of the Stackable Data Platform, how to install and manage it as well as some tutorials.
 
-
-[NOTE]
-.Our second release - September 2022
-====
-We are proud to announce our second public release!
-
-Please read the xref:release_notes.adoc[release notes] to read up on the details.
-====
-
-
-++++
-<br>
-++++
-
-++++
-<div class="boxes two-column">
-++++
-
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-<div class="box">
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-
 ++++
 <h3>Introduction</h3>
 ++++