Create new make target sync_xlsx

Checking in an XLSX spreadsheet into CPONT repo does not work, as @james told us multiple times.

We need to adopt his https://github.com/obi-ontology/obi/blob/master/src/scripts/xlsx2tsv.py script

Integrated like this in a makefile: https://github.com/obi-ontology/obi/blob/master/Makefile#L130

Concrete steps:

1. Copy the xlsx2tsv script from OBI repo to src/scripts/
2. Create new make goal in src/ontology/cpont.Makefile called sync_xlsx that calls the script, get inspired here: https://github.com/obi-ontology/obi/blob/master/Makefile#L130
3. Run test: run.bat make sync_xlsx should collect all the tables managed by the xlsx as sheets into the xlsx file
4. Make merge request and assign me as a reviewer