HFP-2444 Prevent max score not being achievable

[otacke]

Currently, there are a couple of scenarios that will lead to a maximum score being computed that is higher than the score that can be achieved. In particular, it's possible that a dropzone is set to only accept one element but two elements require to be put onto that dropzone without any alternative. In that case, Drag and Drop currently will issue two points possible while one can only get one.

While there may be cases for Kobayashi-Maru tests, it probably makes more sense to never set the maximum score higher than the achievable score.

When merged in, the calculateMaxScore function will fix this problem. Papi Jo has already verified this claim for a couple of different scenarios, please cmp. https://h5p.org/node/1187680.

[BiLachner]

Hi,
the error still seems to exist.
Here a freshly created quiz, newest updates of the moodle-Plugin are installed: Download

Here the result:

And the "Solution":