Update gentoo overlay URL

[catfromplan9]

I was doing a live rebuild on my gentoo system when I saw that this package was updated. I went and checked and noticed that there is a gentoo overlay listed for it now. I have had this packaged on my overlay for quite a while now. The gentoo package which is advertised in the README is extremely poorly made.

This ebuild would throw a dozen errors in something like pkgcheck, which is gentoo's utility checking the syntax for ebuilds to ensure they are properly written. LICENSE="MIT License" is wrong, according to SPDX it should be LICENSE="MIT", and this will lead to the software being unable to be installed unless you accept the license manually by editing /etc/portage/package.license (gentoo sees it as a proprietary package). Furthermore, it's a 9999 ebuild, so similar to -git on AUR, yet it is pulling a particular commit to build

COMMIT="6a133be3235177801e2aaf80619afcd40071c9c0"

SRC_URI="
	https://github.com/dtinth/comic-mono-font/archive/${COMMIT}.zip -> ${P}.zip
"

This also violates gentoo policy regarding how things can be packaged, a 9999 ebuild must provide the latest commit of a package using git-r3 eclass (or whatever source control is being used) which mine does. There is also a leading space and unicode characters in DESCRIPTION, DESCRIPTION is too long, there is an empty IUSE for no reason, and so on. There is also lots of fluff lines that are entirely unnecessary and do nothing.

I regularly ensure my ebuilds are properly formatted and have no syntax errors or more severe errors, especially not things as egregious as these. I advise you to merge this PR to resolve all these problems, thanks. Have a nice day.