Update master branch version description to latest version 1.1.0-beta.2 (#334)

Co-authored-by: Benedikt Menne <[email protected]>

Author: bmenne-dspace

docs/index.adoc

@@ -15,7 +15,7 @@
 :favicon: images/favicon.ico
 :icons: font
 :revdate: unreleased
-:revnumber: 1.1.0-beta.1
+:revnumber: 1.1.0-beta.2
 
 include::0____preamble.adoc[]