Remove tags from README

The tags framework has been discontinued for a long time.

https://governance.openstack.org/tc/reference/tags/

https://governance.openstack.org/tc/resolutions/20211224-tags-framework-removal.html

Change-Id: I0c8789806dd3a9b18706eaf4b19cf0e4fe7533e7

Author: anfimovir

README.rst

@@ -1,16 +1,11 @@
-========================
-Team and repository tags
-========================
+==========
+CloudKitty
+==========
 
 .. image:: https://governance.openstack.org/tc/badges/cloudkitty.svg
-    :target: https://governance.openstack.org/tc/reference/tags/index.html
 
 .. Change things from this point on
 
-==========
-CloudKitty
-==========
-
 .. image:: doc/source/images/cloudkitty-logo.png
     :alt: cloudkitty
     :align: center