[ENHANCEMENT] Add support for BETA and RC

[hackacad]

Support for BETA* and RC* would be great.

pkgbasify/pkgbasify.lua

Line 223 in ee835d5

if branch == "RELEASE" then

if branch:match("^RELEASE") or branch:match("^BETA") or branch:match("^RC") then
		return "pkg+https://pkg.FreeBSD.org/${ABI}/base_release_" .. minor

14.3-RC1 worked without any issues.

[ring-pete]

+1 on my end as well, this will really people who are testing before the 14.3 goes live.