mail/fetchmail: update to 6.4.12 (regression fixes)

Fixes these regressions:

• Misleading false complaints that TLSv1.3 support were missing from the system but still auto-negotiating it (broken in 6.4.9, fixed in 6.4.11).
• README contained NEWS fragments (broken since c. 1 year/c. 6.4.2, fixed in 6.4.12) instead of the actual contents. (This was also the reason to skip 6.4.11).

For the potential MFH 6.4.8 -> 6.4.12, 6.4.9 also
adds to the manual page which has is used for fingerprints, MD5,
and adds a Romanian-language translation by Florentina Musat.

PR: 249009
Approved by: Corey Halpin (maintainer)
MFH: 2020Q3 (manpage, README fixes, added translation)