Remove SatelliteImage class for reading sensor metadata in favor of a Raster option

[rhugonnet]

This PR removes the SatelliteImage class (child of Raster) and replaces it by a parse_sensor_metadata argument (False by default) and silent argument of Raster.__init__, as discussed in #532.

All sensor metadata is saved in Raster.tags along other metadata, with practical datatypes when relevant (datetime, float). By necessity, the tags metadata is written as str on disk, so this PR also adds a function that automatically "decodes'" sensor metadata to convert it back to its datatype.
In short, the sensor metadata can be written/read from file consistently!

Additionally, this PR removes the old option of Vector.reproject() accepting a str as reference (which is inconsistent with the rest of the package that never accepts strings as method input), as it sometimes triggered errors depending on fiona/pyogrio reading.
We could add back this functionality consistently everywhere after solving #595, if desired.

Resolves #626
Resolves #532

TO-DO

• Add new tests for parse_sensor_metadata behaviour,
• Test if tags are conserved after writing to file and re-reading.