`mimetypes.py` uses deprecated "application/javascript"

[ppena-LiveData]

The _types_map_default values for JavaScript use the deprecated "application/javascript" value. RFC 9239 as well as http://www.iana.org/assignments/media-types (which is referenced in mimetypes.py) both say that type/subtype name is obsolete and should be replaced with "text/javascript".

[ambv]

Thanks for this! We're not backporting to 3.11 or 3.10 to avoid confusion. This change will land in Python 3.12.