Dynamic loading of the list of available translations

[cameel]

Currently the bot from #12 has the list of enabled repositories hard-coded in its workflow file. It would be more convenient if it could construct it automatically based on what JSON files are present in langs/.

[monjikura]

Currently the bot from #12 has the list of enabled repositories hard-coded in its workflow file. It would be more convenient if it could construct it automatically based on what JSON files are present in langs/.