chore: run pycodestyle on the whole of changed files

Author: edbjunwang

.github/workflows/python-codestyle.yml

@@ -32,5 +32,5 @@ jobs:
           git checkout $GITHUB_BASE_REF
           echo "head ref: $GITHUB_HEAD_REF"
           git checkout $GITHUB_HEAD_REF
-          git --no-pager diff $GITHUB_BASE_REF $GITHUB_HEAD_REF --name-only |grep ".py$" |xargs git --no-pager diff $GITHUB_BASE_REF $GITHUB_HEAD_REF | pycodestyle --show-source --diff
+          git --no-pager diff $GITHUB_BASE_REF $GITHUB_HEAD_REF --name-only |grep ".py$" |xargs pycodestyle --show-source