Add update action to Porting/checkAUTHORS.pl

Fixes #17206

AUTHORS can now be updated by 'Porting/checkAUTHORS.pl' using
the new 'update' action.

Example: perl Porting/checkAUTHORS.pl --update --from=v5.31.6

The changes to the file AUTHORS is better read by ommitting whitespaces.
The changes to AUTHORS are the following:
- authors are sorted
- some emails changed to reflect the preferred email set in the <DATA> section
of checkAUTHORS.pl

When detecting a new author, we will list the GitHub account instead of the email.
Anyone can replace his email by the GitHub account by directly editing AUTHORS file.

Note that the <DATA> section has been adjusted to accomodate several
existing emails in the AUTHORS file to avoid selecting a different email.

'Hio' was listed twice and we preserved the preferred email address.

Author: atoomic