Fix mb.py presubmit issues.

* Add a config file for python formatting (.style.yapf).
* Change the default indentation from 4 spaces to 2 spaces.
* Run 'git cl format --python' on a few python files.

Bug: webrtc:13413
Change-Id: Ia71135131276c2c499b00032d57ad16ee5200a5c
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/238982
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Reviewed-by: Christoffer Jansson <jansson@google.com>
Reviewed-by: Henrik Andreassson <henrika@webrtc.org>
Commit-Queue: Jeremy Leconte <jleconte@google.com>
Cr-Commit-Position: refs/heads/main@{#35500}
diff --git a/pylintrc b/pylintrc
index f26c84a..e353d9e 100644
--- a/pylintrc
+++ b/pylintrc
@@ -97,6 +97,9 @@
 # Maximum number of lines in a module
 max-module-lines=1000
 
+# We use two spaces for indents, instead of the usual four spaces or tab.
+indent-string='  '
+
 
 [BASIC]
 
@@ -192,10 +195,6 @@
 
 [CLASSES]
 
-# List of interface methods to ignore, separated by a comma. This is used for
-# instance to not check methods defines in Zope's Interface base class.
-ignore-iface-methods=isImplementedBy,deferred,extends,names,namesAndDescriptions,queryDescriptionFor,getBases,getDescriptionFor,getDoc,getName,getTaggedValue,getTaggedValueTags,isEqualOrExtendedBy,setTaggedValue,isImplementedByInstancesOf,adaptWith,is_implemented_by
-
 # List of method names used to declare (i.e. assign) instance attributes.
 defining-attr-methods=__init__,__new__,setUp