Upgrade pylint and astroid to avoide false positive E1111

See pylint-dev/pylint#2694 for details.
http://ci.mxnet.io/blue/organizations/jenkins/GluonNLP-py3-master-gpu-integration/detail/PR-836/1/
for an example how the bug affects us.

Author: leezu

env/cpu/py3-master.yml

@@ -4,7 +4,7 @@ dependencies:
   - python=3.6
   - pip=18.1
   - perl
-  - pylint=1.9.2
+  - pylint=2.3.1
   - flake8
   - sphinx=1.7.7
   - spacy
@@ -16,7 +16,7 @@ dependencies:
   - pytest-xdist<2
   - regex
   - pip:
-    - pylint-quotes<0.2
+    - pylint-quotes==0.2.1
     - mxnet-mkl>=1.5.0b20190407
     - sacremoses
     - sentencepiece<0.2

env/cpu/py3.yml

@@ -4,7 +4,7 @@ dependencies:
   - python=3.6
   - pip=18.1
   - perl
-  - pylint=1.9.2
+  - pylint=2.3.1
   - flake8
   - sphinx=1.7.7
   - spacy
@@ -26,7 +26,7 @@ dependencies:
   - ipykernel
   - regex
   - pip:
-    - pylint-quotes<0.2
+    - pylint-quotes==0.2.1
     - mxnet-mkl>=1.4.1
     - sacremoses
     - sentencepiece<0.2

env/gpu/py3-master.yml

@@ -4,7 +4,7 @@ dependencies:
   - python=3.6
   - pip=18.1
   - perl
-  - pylint=1.9.2
+  - pylint=2.3.1
   - flake8
   - sphinx=1.7.7
   - spacy

env/gpu/py3.yml

@@ -4,7 +4,7 @@ dependencies:
   - python=3.6
   - pip=18.1
   - perl
-  - pylint=1.9.2
+  - pylint=2.3.1
   - flake8
   - sphinx=1.7.7
   - spacy
@@ -26,7 +26,7 @@ dependencies:
   - ipykernel
   - regex
   - pip:
-    - pylint-quotes<0.2
+    - pylint-quotes==0.2.1
     - mxnet-cu92mkl>=1.4.1
     - sacremoses
     - sentencepiece<0.2