Adding "_" , a number and other non-letter character at the end of a dimension.json name will make it an invalid .json (Datapack)

The main problem is related on the title (and related with adding new dimensions with datapacks). To recreate this issue, download the datapack that I provided, and if you want you can create a world with that datapack to verify that it's currently working and adding a new dimension called "pru_eba". Then, go to the dimensions/minecraft and rename the pru_eba.json to pru_eba_.json, for example. Try to use the modified datapack and you will se that the new added dimension isn't working.