Add new port www/geckodriver

[krion]

Summary

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=216696

This program provides the HTTP API described by the WebDriver protocol to
communicate with Gecko browsers, such as Firefox. It translates calls into the
Marionette automation protocol by acting as a proxy between the local- and
remote ends.

WWW: https://github.com/mozilla/geckodriver

[mat]

www/geckodriver/Makefile

20 ↗

(On Diff #24965)

s/ +=/=/

[krion]

Fixed assignment for MAKE_ENV

[krion]

Mat, can you approve it? Thanks.