Add python 3.14 musl distributions

[Finkregh]

It seems the musl builds for 3.14 are missing:

97a354aefc2e:/# uv --version
uv 0.6.6
97a354aefc2e:/# cat /etc/os-release
NAME="Alpine Linux"
ID=alpine
VERSION_ID=3.21.2
PRETTY_NAME="Alpine Linux v3.21"
HOME_URL="https://alpinelinux.org/"
BUG_REPORT_URL="https://gitlab.alpinelinux.org/alpine/aports/-/issues"
97a354aefc2e:/# uv python list --all-versions --all-platforms --all-arches --only-downloads | grep 3.13 | grep musl
cpython-3.13.2-linux-x86_64_v4-musl                    <download available>
cpython-3.13.2-linux-x86_64_v3-musl                    <download available>
cpython-3.13.2-linux-x86_64_v2-musl                    <download available>
cpython-3.13.2-linux-x86_64-musl                       <download available>
97a354aefc2e:/# uv python list --all-versions --all-platforms --all-arches --only-downloads | grep 3.14 | grep musl

Thanks!

[zanieb]

We haven't added support yet (briefly noted in #443)