Add latest version tag of a milestone

[PhrozenByte]

Currently one is required to know the latest stable release of a given OpenWrt milestone to build an image (i.e. using the imagebuilder container; the same could be done for the other containers, if applicable) with the latest stable patch version. Currently one must research the latest stable patch release first and then pull the matching version tag:

docker run --rm -v "$(pwd)"/bin/:/builder/bin -it openwrt/imagebuilder:ath79-generic-23.05.3

Instead of manually researching the latest patch version, it would be great if we could get a <milestone>-latest alias tag, like the following (or similar):

docker run --rm -v "$(pwd)"/bin/:/builder/bin -it openwrt/imagebuilder:ath79-generic-23.05-LATEST

I'm aware of the ath79-generic-23.05-SNAPSHOT resp. ath79-generic-openwrt-23.05 branch tags, but these naturally don't give the latest stable patch version, but the current snapshot of the milestone.