Remove spaces at end of line in all python files

These are useless, git complain about them and they cause unnecessary diffs when having editor configured to automatically remove spaces at end of lines, so let's do a big commit to remove them all at once

See merge request !1672
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Status Job ID Name Coverage
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failed ERP5.CodingStyleTest-Master

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passed ERP5.PerformanceTest-Master

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failed ERP5.UnitTest-Master

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failed ERP5.UnitTest-Master.Medusa

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passed SlapOS.Eggs.UnitTest-Master.Python2

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passed SlapOS.Eggs.UnitTest-Master.Python3

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passed ERP5.CodingStyleTest-Master

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passed ERP5.PerformanceTest-Master

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passed SlapOS.Eggs.UnitTest-Master.Python2

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passed SlapOS.Eggs.UnitTest-Master.Python3

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