docs: Add 1.1.0 release notes

Author: Techassi

docs/modules/stackablectl/partials/release-notes/release-1.1.0.adoc

@@ -0,0 +1,7 @@
+== 1.1.0
+
+* We now support idempotent Helm installations for demos and stacks.
+  See https://github.com/stackabletech/stackable-cockpit/pull/386[stackable-cokcpit#386].
+* Ignore failed re-application of Jobs due to immutability in demo and stack installations.
+  The user is now asked if these be deleted or recreated.
+  See https://github.com/stackabletech/stackable-cockpit/pull/386[stackable-cokcpit#386].