Bug 1698825 [wpt PR 28070] - Update pycodestyle to 2.7.0, a=testonly

Automatic update from web-platform-tests
Update pycodestyle from 2.6.0 to 2.7.0 (#28070)

Co-authored-by: Stephen McGruer <smcgruer@chromium.org>
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wpt-commits: f6a1fd063fd77ea5865c82682458ae4fb7d04bb3
wpt-pr: 28070

testing/web-platform/tests/tools/requirements_flake8.txt

@@ -1,4 +1,4 @@
 flake8==3.9.0
-pycodestyle==2.6.0
+pycodestyle==2.7.0
 pyflakes==2.3.0
 pep8-naming==0.11.1