Docs: What's new & Upgrade guide v11.6 (#101479)

* Docs: What's new & Upgrade guide v11.6

* Adding alerting entries

* adding new entries

* updating entries and initial text from website PR

* Reorder changelog entries

* adjusting front matter spacing for product labels

* adding missing space

---------

Co-authored-by: Mitch Seaman <mjseaman@users.noreply.github.com>
Co-authored-by: Jack Baldry <jack.baldry@grafana.com>

docs/sources/upgrade-guide/upgrade-v11.6/index.md

@@ -0,0 +1,22 @@
+---
+description: Guide for upgrading to Grafana v11.6
+keywords:
+  - grafana
+  - configuration
+  - documentation
+  - upgrade
+  - '11.6'
+title: Upgrade to Grafana v11.6
+menuTitle: Upgrade to v11.6
+weight: 600
+---
+
+# Upgrade to Grafana v11.6
+
+{{< docs/shared lookup="upgrade/intro.md" source="grafana" version="<GRAFANA_VERSION>" >}}
+
+{{< docs/shared lookup="back-up/back-up-grafana.md" source="grafana" version="<GRAFANA_VERSION>" leveloffset="+1" >}}
+
+{{< docs/shared lookup="upgrade/upgrade-common-tasks.md" source="grafana" version="<GRAFANA_VERSION>" >}}
+
+## Technical notes