Describe the bug

r.in.pdal fails to import LAZ files:

Reading data...
terminate called after throwing an instance of 'pdal::pdal_error'
  what():  writers.grassbinning: Missing value for positional argument 'filename'.

To Reproduce
Steps to reproduce the behavior:

1. Download sample data https://ags.cuzk.cz/geoprohlizec/?atom=dmr5g (or use attached sample: KRAV59.zip)
2. Create location in EPSG 5514
3. Run r.in.pdal -oe input=06/dmr5g/KRAV59.laz output=KRAV59 resolution=1
4. See error

Expected behavior

The same sample data is successfully imported when GRASS is compiled with PDAL 2.6.

System description (please complete the following information):

• Operating System: Debian Linux
• GRASS GIS version main