incomplete board information prevents further work

[TheIsotopes]

@klutvott123 During a test on a MatekH743 i noticed that the first run of the scripts after downloading the boardinfo fails.
After looking at the generated file, i noticed that an entry in the manufacturer_id is empty and that it breaks the first run of the scripts.
After entering manufacturer_id MTKS in the cli and restarting the script everything runs without problems.

imo should break this on all other legacy target as well.
pls can you check this ?!

[klutvott123]

Fixed in #412. Test version included in PR.
This should have been able to handle empty strings, but wasn't because I forgot to wrap them in "" when writing to file.
Thanks for testing and reporting this 👍