Fix some business template update bugs

Several bug fixes for business template update bugs, including a fix for the problem preventing to update erp5_accounting_l10n_fr

See merge request !1112
17 jobs for master in 0 seconds
Status Job ID Name Coverage
  External
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passed ERP5.PerformanceTest-Master

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passed SlapOS.Eggs.UnitTest-Master.Python3

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passed SlapOS.Eggs.UnitTest-Master.Python3

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