sysutils/beats7: Update to 7.10.1

Changelog at:
https://www.elastic.co/guide/en/beats/libbeat/7.10/release-notes-7.10.1.html

And while here, also reformat Makefile according to portfmt and portclippy

Reviewed by: osa (mentor)
Approved by: osa (mentor)
Differential Revision: https://reviews.freebsd.org/D27822