rm trailing whitespace from salt/states/file.py

************* Module salt.states.file
salt/states/file.py:954: [C0303(trailing-whitespace), ] Trailing whitespace
can't fix withoput affecting api
Merge pull request #10913 from cvrebert/patch-1

rm trailing whitespace from salt/states/file.py
/probably/ okay
Merge branch 'develop' into with-pylint-pragmas