README: fix url links to github badges

Author: Lukas955

README.rst

@@ -165,7 +165,7 @@ be useful also for other users? Please, share your experiences and thoughts.
     or temporarily change an environment variable
     "``export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib64/``"
 
-.. |BuildMaster| image:: https://github.com/Lukas955/ipfixcol2/workflows/Build%20and%20tests/badge.svg?branch=master
+.. |BuildMaster| image:: https://github.com/CESNET/ipfixcol2/workflows/Build%20and%20tests/badge.svg?branch=master
    :target: https://github.com/CESNET/ipfixcol2/tree/master
-.. |BuildDevel| image:: https://github.com/Lukas955/ipfixcol2/workflows/Build%20and%20tests/badge.svg?branch=devel
+.. |BuildDevel| image:: https://github.com/CESNET/ipfixcol2/workflows/Build%20and%20tests/badge.svg?branch=devel
    :target: https://github.com/CESNET/ipfixcol2/tree/devel