Generating import-expectations.json can cause trailing whitespaces, in older versions of Python, this causes noise in WPT import diffs. This is because older versions of python have `separators=(', ', ': ')` as default separators instead of `separators=(',', ': ')`.
<rdar://problem/102940524>
Pull request: https://github.com/WebKit/WebKit/pull/7121
Committed 257335@main (06d28085c8e7): <https://commits.webkit.org/257335@main> Reviewed commits have been landed. Closing PR #7121 and removing active labels.