sysutils/logstash7: Update to 7.10.1

Changelog at:
https://www.elastic.co/guide/en/logstash/7.10/logstash-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/D27821