docs: upgrade guide refactor organizes releases into their own pages; moves upgrade guide to the root (#62402)

* organizes releases into their own pages; moves upgrade guide to the root

* adds and removes aliases

* Update docs/sources/upgrade-guide/upgrade-v8.0/index.md

Co-authored-by: Jack Baldry <jack.baldry@grafana.com>

* Update docs/sources/upgrade-guide/upgrade-v8.0/index.md

Co-authored-by: Jack Baldry <jack.baldry@grafana.com>

* Update docs/sources/upgrade-guide/upgrade-v8.0/index.md

Co-authored-by: Jack Baldry <jack.baldry@grafana.com>

* Update docs/sources/upgrade-guide/upgrade-v9.3/index.md

Co-authored-by: Jack Baldry <jack.baldry@grafana.com>

* Update docs/sources/shared/upgrade/upgrade-common-tasks.md

Co-authored-by: Jack Baldry <jack.baldry@grafana.com>

* Update docs/sources/shared/upgrade/upgrade-common-tasks.md

Co-authored-by: Jack Baldry <jack.baldry@grafana.com>

* Update docs/sources/shared/upgrade/upgrade-common-tasks.md

Co-authored-by: Jack Baldry <jack.baldry@grafana.com>

* corrects relrefs

---------

Co-authored-by: Jack Baldry <jack.baldry@grafana.com>

docs/sources/setup-grafana/installation/windows/index.md

@@ -10,8 +10,7 @@ weight: 500
 
 You can either download the Windows installer package or a standalone Windows binary file.
 
-Read [Upgrading Grafana]({{< relref "../../upgrade-grafana/" >}}) for tips and guidance on updating an existing
-installation.
+Read [Upgrading Grafana]({{< relref "../../../upgrade-guide/" >}}) for tips and guidance on updating an existing installation.
 
 1. Navigate to [Download Grafana](https://grafana.com/grafana/download?platform=windows).
 1. Select a Grafana version you want to install.