NaN in weekly goal

[jaragunde]

Open phpreport in 31st Dec, 2018; the displayed weekly goal is "NaN".

I suspect the problem is that 31st Dec is part of 2018 but belongs to week 1, 2019. The calculated goal for the rest of week 1, 2019 should be checked too.

[jaragunde]

Fixed by this commit, reviewed in PR #520. Mind you that the result provided is 0 and not the correct one, but we'd need more work and will be revisited in #521.

commit 526d37719cd4ae447c1fb81e57428de4b33f62d8
Author: Ana Rute Mendes <ana@igalia.com>
Date:   Wed Sep 29 16:39:35 2021 -0300

    Fix weekly goal calc if in last week of the year
    
    If the week in case is the last week of the year,
    this method would fail because weeksTillEndOfJourneyPeriod
    is 0, causing a division by 0 exception
    
    Fixes https://github.com/Igalia/phpreport/issues/432