Remove dots in config names
_The documentation is not available anymore as the PR was closed or merged._ Closing in favor of https://github.com/huggingface/datasets/pull/4367
20+ datasets have dots in their config names. However it causes issues with the YAML tags of the dataset cards since we can't have dots in YAML keys.

This is related to https://github.com/huggingface/datasets/pull/2362 (internal https://github.com/huggingface/moon-landing/issues/946).

Also removing the dots in the config names would allow us to merge https://github.com/huggingface/datasets/pull/4302 which removes a hack that replaces all the dots by underscores in the YAML tags.

I also added a test in the CI that checks that all the YAML tags to make sure that:
- they can be parsed using a YAML parser
- they contain only valid YAML tags like `languages` or `task_ids`
- they contain valid config names (no invalid characters `<>:/\|?*.`)