mail/fetchmail: update to 6.4.30.

FreeBSD ports relevant changes since 6.4.28:

Translation updates for:

• ro: Remus-Gabriel Chelu [Romanian]
• vi: Trần Ngọc Quân [Vietnamese]

PR: 263595
Approved by: Corey Halpin (maintainer)
MFH: 2022Q2

(cherry picked from commit 726c185cd8333baba5e8c67ccb1186416b83272b)