Merge pull request MicrosoftDocs#1174 from sptramer/toc/release-notes-title

Fix release notes title in ToC

Author: sptramer

docs-conceptual/azps-2.4.0/toc.yml

@@ -81,7 +81,7 @@
     displayName: database, nosql, mongodb, couchdb
 - name: Release notes
   items:
-  - name: Az 2.1.0 release notes
+  - name: Release notes
     href: release-notes-azureps.md
   - name: Az 2.0.0 breaking changes
     href: migrate-az-2.0.0.md