Merge pull request #1780 from freenas/docs549-tn11.3-u2.2docs-11.3angular

DOCS-549: remove preview note from TrueNAS guide intro

Author: Mrt134

userguide/tn_intro.rst

@@ -1,8 +1,3 @@
-.. tip:: This guide is a **preview** of the upcoming 11.3-U2 release of
-   %brand%. |Web-UI| elements documented in this guide are subject to
-   change before the public release of %brand% 11.3-U2.
-
-
 Copyright iXsystems 2011-|copyright-year|
 
 %brand% and the %brand% logo are registered trademarks of iXsystems.