chore: remove coveralls badge

README.md

@@ -1,7 +1,6 @@
 [![Documentation Status](https://img.shields.io/readthedocs/okama.svg?style=popout)](http://okama.readthedocs.io/)
 [![Python](https://img.shields.io/badge/python-v3-brightgreen.svg)](https://www.python.org/)
 [![PyPI Latest Release](https://img.shields.io/pypi/v/okama.svg)](https://pypi.org/project/okama/)
-[![Coverage](https://coveralls.io/repos/github/mbk-dev/okama/badge.svg?branch=master)](https://coveralls.io/github/mbk-dev/okama?branch=master)
 [![License](https://img.shields.io/pypi/l/okama.svg)](https://opensource.org/licenses/MIT)
 [![Open In Collab](https://colab.research.google.com/assets/colab-badge.svg)](https://colab.research.google.com/github/mbk-dev/okama/blob/master/examples/01%20howto.ipynb)
 

docs/index.rst

@@ -12,12 +12,12 @@
             <a href="https://pypi.org/project/okama/">
                 <img src="https://img.shields.io/badge/pypi-v1.0.1-brightgreen.svg"
                     alt="pypi"></a> &nbsp;
-            <a href='https://coveralls.io/github/mbk-dev/okama?branch=master'>
-                <img src='https://coveralls.io/repos/github/mbk-dev/okama/badge.svg?branch=master'
-                alt='Coverage Status' /></a>
             <a href="https://opensource.org/licenses/MIT">
                 <img src="https://img.shields.io/badge/license-MIT-brightgreen.svg"
                     alt="MIT license"></a> &nbsp;
+            <a href="https://colab.research.google.com/github/mbk-dev/okama/blob/master/examples/01%20howto.ipynb">
+                <img src="https://colab.research.google.com/assets/colab-badge.svg"
+                    alt="MIT license"></a> &nbsp;
         </p>
     </embed>