Meta: Use pip to install pylint
Meta: Use pip to install pylint

pylint is available for install using pip which is the preferred method
of install for python packages over apt-get. Using apt-get to install
pylint often results in different versions of pylint being installed on
different systems. Using pip to install pylint will ensure that same
version is being used on all systems.

Test plan:

(Manual) Check the version number of pylint installed using
"pylint --version". Now, run /meta/install_devtools.sh. This should
update pylint to the latest version. Check version number again and
ensure that the latest version is installed.

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