[Merge] lp:~bhavesh-goyal093/postorius/fixed-postorius-method-decorators into lp:postorius

[Terri]

The update seems to have fixed the test errors I saw earlier; thanks!
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https://code.launchpad.net/~bhavesh-goyal093/postorius/fixed-postorius-method-decorators/+merge/256037
Your team Mailman Coders is requested to review the proposed merge of lp:~bhavesh-goyal093/postorius/fixed-postorius-method-decorators into lp:postorius.