Simplifies test requirements

Author: edumco

tests/requirements.txt

@@ -1,33 +1,8 @@
-# Dependency trees generated on python:3.8.3-debian-sim
+# Fixed versions only on high level packages
+# This allows pip to resolve compatible version
+# The same aproach is not recommended on build requirements
 
-# Pytest
-    attrs==20.3.0
-    more-itertools==8.7.0
-    packaging==20.9
-    pluggy==0.13.1
-    py==1.10.0
-    pyparsing==2.4.7
-    six==1.15.0
-    wcwidth==0.2.5
-pytest==6.2.2
-
-# Pylama
-    pycodestyle==2.6.0
-    pydocstyle==5.1.1
-    pyflakes==2.2.0
+bandit==1.7.0
 pylama==7.7.1
-
-# Pytest-xdist
-  execnet==1.8.0
-    apipkg==1.5
-  pytest-forked==1.3.0
+pytest==6.2.2
 pytest-xdist==2.2.1
-
-# Bandit
-  GitPython==3.1.13
-    gitdb==4.0.5
-      smmap==4.0.0
-  PyYAML==5.4.1
-  stevedore==3.3.0
-    pbr==5.5.1
-bandit==1.7.0