Revert "Activates testing for python2 again."

This reverts commit 4795213.

.travis.yml

@@ -10,7 +10,6 @@ language: python
 cache: pip
 
 python:
-  - "2.7"
   - "3.6"
   - "3.7"
   - "3.8"

tox.ini

@@ -6,7 +6,7 @@
 [tox]
 skip_missing_interpreters = true
 envlist =
-    docs,py27,py36,py37,py38,pypy3
+    docs,py36,py37,py38,pypy3
 
 logstash_async_modules = logstash_async tests
 
@@ -23,20 +23,6 @@ commands =
     # unit tests
     {envbindir}/python -m unittest discover --start-directory tests --pattern '*_test.py'
 
-[testenv:py27]
-# same as above except for skipping PyLint on Python 2.7 as there are different,
-# probably false-positive errors and tricky requirement of old PyLint version
-# for Python 2.7.
-deps =
-    flake8
-    isort
-commands =
-    # linting and code analysis
-    {envbindir}/flake8 {[tox]logstash_async_modules}
-    {envbindir}/isort --check-only --diff --recursive {[tox]logstash_async_modules}
-    # unit tests
-    {envbindir}/python -m unittest discover --start-directory tests --pattern '*_test.py'
-
 [testenv:docs]
 basepython = python3
 deps =