[welcomepage] fixes #18118 remove last item causes a crash

[slarosa]

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[nyalldawson]

Shouldn't this be beginRemoveRows/endRemoveRows?

[slarosa]

@nyalldawson yes, my first fix was that, but it crashes yet, so I tried to reset model. Testing again the beginRemoveRowshas worked, maybe a local and temporary problem :-). I am addressing your comment.

Thanks for reviewing.

[nyalldawson]

Let's try this fix - I think if there's still a crash there's another issue present too.