Fixed dependency issues from previous commit

Details:

* The increase of tox to 3.21.0 in the previous commit causes a version conflict
  on Python 3.6 with minimum package levels, since pluggy 0.7.1 violates the
  tox requirement of pluggy>=0.12.0. Fixed that by increasing the minimum version
  of pluggy to 0.13.1 for all Python versions (for simplicity).

* The increase of tox to 3.21.0 in the previous commit causes a version conflict
  on Python>=3.6 with minimum package levels just on Windows, because tox
  requires colorama>=0.4.1 but the minimum is 0.4.0. Fixed that by increasing
  the minimum version of colorama to 0.4.1 on Python >=3.5.

Signed-off-by: Andreas Maier <andreas.r.maier@gmx.de>

Author: andy-maier

dev-requirements.txt

@@ -133,10 +133,11 @@ readme-renderer>=23.0; python_version >= '3.5'
 pytz>=2016.10; python_version <= '3.9'
 pytz>=2019.1; python_version >= '3.10'
 
-# colorama (used by TBD)
+# colorama (used by tox, pytest)
 # colorama 0.4.0 removed support for Python 3.4
+# tox 3.21.0 depends on colorama>=0.4.1 for platform_system == "Windows"
 colorama>=0.3.9,<0.4.0; python_version <= '3.4'
-colorama>=0.4.0; python_version >= '3.5'
+colorama>=0.4.1; python_version >= '3.5'
 
 
 # Additional indirect dependencies are not specified in this file:

minimum-constraints.txt

@@ -121,10 +121,8 @@ virtualenv==20.1.0; python_version >= '3.5'
 # packaging (used by pytest)
 packaging==17.0
 
-# pluggy (used by pytest)
-# Pluggy 0.12.0 has a bug causing pytest plugins to fail loading on py38
-pluggy==0.7.1; python_version >= '2.7' and python_version <= '3.6'
-pluggy==0.13.0; python_version >= '3.7'
+# pluggy (used by pytest, tox)
+pluggy==0.13.1
 
 # six (used by virtualenv, tox, probably others)
 # virtualenv 20.0 requires six>=1.12.0 on py>=3.8
@@ -212,10 +210,10 @@ readme-renderer==23.0
 pytz==2016.10; python_version <= '3.9'
 pytz==2019.1; python_version >= '3.10'
 
-# colorama (used by TBD)
+# colorama (used by tox, pytest)
 # colorama 0.4.0 removed support for Python 3.4
 colorama==0.3.9; python_version <= '3.4'
-colorama==0.4.0; python_version >= '3.5'
+colorama==0.4.1; python_version >= '3.5'
 
 
 # Other indirect dependencies (not in any requirements file):

test-requirements.txt

@@ -34,10 +34,11 @@ virtualenv>=20.1.0; python_version >= '3.5'
 # packaging (used by pytest)
 packaging>=17.0
 
-# pluggy (used by pytest)
+# pluggy (used by pytest, tox)
 # Pluggy 0.12.0 has a bug causing pytest plugins to fail loading on py38
-pluggy>=0.7.1; python_version >= '2.7' and python_version <= '3.6'
-pluggy>=0.13.0; python_version >= '3.7'
+# pytest 4.3.1 depends on pluggy>=0.7
+# tox 3.21.0 depends on pluggy>=0.12.0
+pluggy>=0.13.1
 
 # six (used by virtualenv, tox, probably others)
 # virtualenv 20.0 requires six>=1.12.0 on py>=3.8