Final fix for pylint issue 4118

Details:

* Pylint issue pylint-dev/pylint#4118 introduced in
  Pylint 2.7.0 was fixed in Pylint 2.10.0.

  This change accomodates the fix by removing the circumvention of
  disabling warning R801 on py<3.6, and by increasing the minimum version
  of Pylint to 2.10.0 for Python >=3.6. The Pylint version with the
  issue is not supported on earlier Python versions.

  No change log entry is needed, since the circumvention was introduced
  in the same package version.

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

Makefile

@@ -238,17 +238,6 @@ pylint_rc_file := pylintrc
 pylint_todo_opts := --disable=fixme
 pylint_no_todo_opts := --enable=fixme
 
-# Disable the similarity checker on pylint <2.10 due to issues #2672, #2673
-ifeq ($(python_mn_version),2.7)
-  pylint_sc_opts := --disable=R801
-else
-  ifeq ($(python_mn_version),3.5)
-    pylint_sc_opts := --disable=R801
-  else
-    pylint_sc_opts :=
-  endif
-endif
-
 # Flake8 config file
 flake8_rc_file := .flake8
 
@@ -837,8 +826,8 @@ else
 	@echo "Makefile: Running Pylint"
 	-$(call RM_FUNC,$@)
 	pylint --version
-	pylint $(pylint_sc_opts) $(pylint_no_todo_opts) --rcfile=$(pylint_rc_file) $(py_src_files)
-	pylint $(pylint_sc_opts) $(pylint_todo_opts) --rcfile=$(pylint_rc_file) $(py_test_files)
+	pylint $(pylint_no_todo_opts) --rcfile=$(pylint_rc_file) $(py_src_files)
+	pylint $(pylint_todo_opts) --rcfile=$(pylint_rc_file) $(py_test_files)
 	echo "done" >$@
 	@echo "Makefile: Done running Pylint"
 endif

dev-requirements.txt

@@ -77,7 +77,7 @@ Babel>=2.7.0
 # Pylint 1.x / astroid 1.x supports py27 and py34/35/36
 # Pylint 2.0 / astroid 2.0 removed py27, added py37
 # Pylint 2.7 / astroid 2.5 removed support for py35
-# Pylint 2.10.0 / astroid 2.7.2 fixes issues in similarity checker (issues #2672, #2673)
+# Pylint 2.7-2.9 had issue https://github.com/PyCQA/pylint/issues/4118 (issues #2672, #2673)
 pylint>=1.6.4,<2.0.0; python_version == '2.7'
 pylint>=2.5.2; python_version == '3.5'
 pylint>=2.10.0; python_version >= '3.6'