Memo: add muparser dependency for GDAL 3.11

[rouault]

Solution to issue cannot be found in the documentation.

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Issue

The VRT driver in 3.11 can compute expression, but requires the "muparser" dependency, already available in conda-forge.
Cf OSGeo/gdal#11635

It can also use "exprtk" , which brings more powerful capabilities, but this causes libgdal binary size to be increase by about 8 MB. To be debated if we want that

Installed packages

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Environment info

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