Remove unneeded `the_geom_webmercator` param from ST_AsMVT
Remove unneeded `the_geom_webmercator` param from ST_AsMVT

That parameter is not needed. As per the documentation:

> geom_name is the name of the geometry column in the row
> data. Default is the first geometry column.

This will let us push-down the whole ST_AsMVT expression to foreign
servers through FDW's.

CartoDB/Windshaft,CartoDB/Windshaft,CartoDB/Windshaft