Cloud pixels are not masked during NDCI calculation

[whatnick]

NDCI Style config in OWS does not mask for cloud.

See detected cloud coverage here.

[robbibt]

These artefacts seem pretty weird too!

[robbibt]

Here's the styling: https://github.com/GeoscienceAustralia/dea-config/blob/master/dev/services/wms/ows_refactored/baseline_satellite_data/sentinel2/style_s2_cfg.py#L204-L253

But I'm a bit confused... if there's no pq_masks flag defined (e.g. like this), where are the transparent pixels coming from in the examples above?