Merge pull request #477 from slayoo/readme_run_pytest

fix links in README

Author: slayoo

README.md

@@ -8,7 +8,7 @@
 [![Travis Build Status](https://img.shields.io/travis/atmos-cloud-sim-uj/PySDM/master.svg?logo=travis)](https://travis-ci.com/atmos-cloud-sim-uj/PySDM)
 [![Github Actions Build Status](https://github.com/atmos-cloud-sim-uj/PySDM/workflows/Build%20Status/badge.svg?branch=master)](https://github.com/atmos-cloud-sim-uj/PySDM/actions)
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-[![Dependabot](https://img.shields.io/static/v1?label=Dependabot&logo=dependabot&color=blue&message=on)](https://github.com/atmos-cloud-sim-uj/PySDM/network/updates)
+[![Dependabot](https://img.shields.io/static/v1?label=Dependabot&logo=dependabot&color=blue&message=on)](https://github.com/atmos-cloud-sim-uj/PySDM/network/dependencies)
 [![Coverage Status](https://codecov.io/gh/atmos-cloud-sim-uj/PySDM/branch/master/graph/badge.svg)](https://codecov.io/github/atmos-cloud-sim-uj/PySDM?branch=master)   
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@@ -142,7 +142,7 @@ attributes = {}
 attributes['volume'], attributes['n'] = ConstantMultiplicity(spectrum=initial_spectrum).sample(n_sd)
 ```
 
-The key element of the PySDM interface is the [``Core``](https://github.com/atmos-cloud-sim-uj/PySDM/blob/master/PySDM/simulation/core.py) 
+The key element of the PySDM interface is the [``Core``](https://github.com/atmos-cloud-sim-uj/PySDM/blob/master/PySDM/core.py) 
   class which instances are used to manage the system state and control the simulation.
 Instantiation of the ``Core`` class is handled by the ``Builder``
   as exemplified below: