[PATCH 1 of 2 stable] docs: remove link to Bitbucket source mirror

[Manuel Jacob]

# HG changeset patch
# User Manuel Jacob <me at manueljacob.de>
# Date 1600197859 -7200
#      Tue Sep 15 21:24:19 2020 +0200
# Branch stable
# Node ID 3124c863cd9eb9959896e8abeef2c08839844319
# Parent  0bca9e828db247730518cbb4fd9225ea42592faf
# EXP-Topic bitbucket_references
docs: remove link to Bitbucket source mirror

diff --git a/README.rst b/README.rst
--- a/README.rst
+++ b/README.rst
@@ -49,9 +49,6 @@
 The latest sources can be obtained from
 https://kallithea-scm.org/repos/kallithea.
 
-The issue tracker and a repository mirror can be found at Bitbucket_ on
-https://bitbucket.org/conservancy/kallithea.
-
 
 Kallithea features
 ------------------