many: remove trailing spaces from non-patch files

[zyga]

There's a billion little trailing spaces all around the tree. Given that many editors automatically remove them, editing an older file might cause a flurry of unrelated changes that should be fixed separately but nobody has bothered to do that yet.

Patch files are excluded as it might cause them not to apply cleanly anymore.

[github-actions[bot]]

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[ernestl]

There's nothing stopping us from adding more of these over time. Maybe we should add a check to the run-checks scripts to prevent that. Also, there's a check that forces edited spread tests to have a details section, so we'll have to add it to some of these. We can split the list and do half of them each so it's not as tedious, if you want

Yes, nice idea to add checks for this!

[zyga]

I will close this, it's not worth fighting over IMO.