[Bug] Error when clicking on a composite traintuple with status failed

[Esadruhn]

Setup

Local deployement of Substra using skaffold
Latest commit on master (tag: 0.0.17)

Description of the bug

On the models page: http://substra-frontend.node-1.com/model
I have a composite traintuple with the status 'failed'. When trying to click on it, the page becomes entirely blank.

Opening the dev tools gives me this error:

react-12ba27.js:2 TypeError: Cannot read property 'hash' of null

This happens with two different failed composite traintuples, no problem with failed traintuples and aggregatetuples, nor with 'done' tuple.

The error seems to come from this:

In case of failure, outHeadModel.outModel and outTrunkModel.outModel are null instead of something like this: outModel: {hash: "77ac6ae57ef74bc465a676e584c71a4d6f0ae083a5bb29e4a532a38e77355732"}

[jmorel]

This has been fixed in #61 :)