Upgrade pylint to version 2.1.1. (#47036)

* Fix issues reported by the latest pylint.
* Split pylint runs into more contexts.
* Upgrade pylint.

test/sanity/pylint/config/ansible-test

@@ -11,6 +11,9 @@ disable=
     too-many-return-statements,
     too-many-statements,
     unused-import,
+    useless-object-inheritance,
+    consider-using-dict-comprehension,
+    consider-using-set-comprehension,
 
 [BASIC]
 

test/sanity/pylint/config/default

@@ -1,11 +1,12 @@
 [MESSAGES CONTROL]
 
 disable=
-    ansible-deprecated-version,
     abstract-method,
     access-member-before-definition,
+    ansible-deprecated-version,
     arguments-differ,
     assignment-from-no-return,
+    assignment-from-none,
     attribute-defined-outside-init,
     bad-continuation,
     bad-indentation,
@@ -14,10 +15,18 @@ disable=
     bare-except,
     blacklisted-name,
     broad-except,
+    c-extension-no-member,
     cell-var-from-loop,
+    chained-comparison,
+    comparison-with-callable,
+    comparison-with-itself,
     consider-iterating-dictionary,
     consider-merging-isinstance,
+    consider-using-dict-comprehension,
     consider-using-enumerate,
+    consider-using-get,
+    consider-using-in,
+    consider-using-set-comprehension,
     consider-using-ternary,
     deprecated-lambda,
     deprecated-method,
@@ -33,13 +42,17 @@ disable=
     global-variable-undefined,
     import-error,
     import-self,
+    inconsistent-return-statements,
+    invalid-envvar-default,
     invalid-name,
     invalid-sequence-index,
     invalid-unary-operand-type,
+    keyword-arg-before-vararg,
     len-as-condition,
     line-too-long,
     literal-comparison,
     locally-disabled,
+    logging-not-lazy,
     method-hidden,
     misplaced-comparison-constant,
     missing-docstring,
@@ -56,7 +69,9 @@ disable=
     old-style-class,
     pointless-statement,
     pointless-string-statement,
+    possibly-unused-variable,
     protected-access,
+    raising-format-tuple,
     redefined-argument-from-local,
     redefined-builtin,
     redefined-outer-name,
@@ -65,6 +80,8 @@ disable=
     relative-import,
     signature-differs,
     simplifiable-if-statement,
+    stop-iteration-return,
+    subprocess-popen-preexec-fn,
     super-init-not-called,
     superfluous-parens,
     too-few-public-methods,
@@ -81,6 +98,8 @@ disable=
     too-many-return-statements,
     too-many-statements,
     trailing-comma-tuple,
+    trailing-comma-tuple,
+    try-except-raise,
     unbalanced-tuple-unpacking,
     undefined-loop-variable,
     unexpected-keyword-arg,
@@ -95,6 +114,9 @@ disable=
     unused-import,
     unused-variable,
     used-before-assignment,
+    useless-import-alias,
+    useless-object-inheritance,
+    useless-return,
     useless-super-delegation,
     wrong-import-order,
     wrong-import-position,