chore: address linter concerns (#508)

Author: texastony

Diff for: decrypt_oracle/test/integration/test_i_decrypt_oracle.py

@@ -25,6 +25,7 @@ def test_all_vectors(vector):
         decrypt_endpoint(),
         data=vector.ciphertext,
         headers={"Content-Type": "application/octet-stream", "Accept": "application/octet-stream"},
+        timeout=120  # 2 minutes
     )
     assert response.status_code == 200
     assert response.content == vector.plaintext

Diff for: decrypt_oracle/tox.ini

@@ -188,8 +188,8 @@ basepython = python3
 deps =
     -rtest/requirements.txt
     {[testenv:generate-pipeline]deps}
-    pyflakes
-    pylint
+    pyflakes==2.5.0
+    pylint==2.15.0
 commands =
     pylint \
         --rcfile=src/pylintrc \

Diff for: src/aws_encryption_sdk/__init__.py

@@ -37,9 +37,9 @@
 )
 
 warnings.warn(
-    'This major version (1.x) of the AWS Encryption SDK for Python has reached End-of-Support.\n' +
-    'It will no longer receive security updates or bug fixes.\n' +
-    'Consider updating to the latest version of the AWS Encryption SDK.',
+    'This major version (1.x) of the AWS Encryption SDK for Python has reached End-of-Support.\n'
+    + 'It will no longer receive security updates or bug fixes.\n'
+    + 'Consider updating to the latest version of the AWS Encryption SDK.',
     DeprecationWarning,
 )
 

Diff for: tox.ini

@@ -132,7 +132,7 @@ commands = {[testenv:test-upstream-requirements-base]commands}
 
 # Linters
 [testenv:flake8]
-basepython = python3
+basepython = python3.8
 deps =
     -rdev_requirements/linter-requirements.txt
 commands =
@@ -164,7 +164,7 @@ commands =
         examples/test/
 
 [testenv:pylint]
-basepython = python3
+basepython = {[testenv:flake8]basepython}
 deps =
     {[testenv]deps}
     -rdev_requirements/linter-requirements.txt
@@ -192,7 +192,7 @@ commands =
         test/integration/
 
 [testenv:blacken-src]
-basepython = python3
+basepython = {[testenv:flake8]basepython}
 deps =
     -rdev_requirements/linter-requirements.txt
 commands =
@@ -206,26 +206,26 @@ commands =
 
 
 [testenv:blacken]
-basepython = python3
+basepython = {[testenv:pylint]basepython}
 deps =
     {[testenv:blacken-src]deps}
 commands =
     {[testenv:blacken-src]commands}
 
 [testenv:black-check]
-basepython = python3
+basepython = {[testenv:pylint]basepython}
 deps =
     {[testenv:blacken]deps}
 commands =
     {[testenv:blacken-src]commands} --diff
 
 [testenv:isort-seed]
-basepython = python3
+basepython = {[testenv:pylint]basepython}
 deps = -rdev_requirements/linter-requirements.txt
 commands = seed-isort-config
 
 [testenv:isort]
-basepython = python3
+basepython = {[testenv:pylint]basepython}
 deps = -rdev_requirements/linter-requirements.txt
 commands = isort -rc \
     src \
@@ -237,12 +237,12 @@ commands = isort -rc \
     {posargs}
 
 [testenv:isort-check]
-basepython = python3
+basepython = {[testenv:pylint]basepython}
 deps = {[testenv:isort]deps}
 commands = {[testenv:isort]commands} -c
 
 [testenv:autoformat]
-basepython = python3
+basepython = {[testenv:pylint]basepython}
 deps =
     {[testenv:blacken]deps}
     {[testenv:isort]deps}
@@ -251,30 +251,30 @@ commands =
     {[testenv:isort]commands}
 
 [testenv:doc8]
-basepython = python3
+basepython = {[testenv:pylint]basepython}
 deps =
     -rdev_requirements/linter-requirements.txt
 commands = doc8 doc/index.rst README.rst CHANGELOG.rst
 
 [testenv:readme]
-basepython = python3
+basepython = {[testenv:pylint]basepython}
 deps = -rdev_requirements/linter-requirements.txt
 commands = python setup.py check -r -s
 
 [testenv:bandit]
-basepython = python3
+basepython = {[testenv:pylint]basepython}
 deps =
     -rdev_requirements/linter-requirements.txt
 commands = bandit -r src/aws_encryption_sdk/
 
 # Prone to false positives: only run independently
 [testenv:vulture]
-basepython = python3
+basepython = {[testenv:pylint]basepython}
 deps = -rdev_requirements/linter-requirements.txt
 commands = vulture src/aws_encryption_sdk/
 
 [testenv:linters]
-basepython = python3
+basepython = {[testenv:pylint]basepython}
 deps =
     {[testenv:flake8]deps}
     {[testenv:pylint]deps}
@@ -289,7 +289,7 @@ commands =
     {[testenv:bandit]commands}
 
 [testenv:linters-tests]
-basepython = python3
+basepython = {[testenv:pylint]basepython}
 deps =
     {[testenv:flake8-tests]deps}
     {[testenv:pylint-tests]deps}
@@ -298,7 +298,7 @@ commands =
     {[testenv:pylint-tests]commands}
 
 [testenv:linters-examples]
-basepython = python3
+basepython = {[testenv:pylint]basepython}
 deps =
     {[testenv:flake8-examples]deps}
     {[testenv:pylint-examples]deps}
@@ -308,13 +308,13 @@ commands =
 
 # Documentation
 [testenv:docs]
-basepython = python3
+basepython = {[testenv:pylint]basepython}
 deps = -rdoc/requirements.txt
 commands =
     sphinx-build -E -c doc/ -b html doc/ doc/build/html
 
 [testenv:serve-docs]
-basepython = python3
+basepython = {[testenv:pylint]basepython}
 skip_install = true
 changedir = doc/build/html
 deps =