There is no ring 0.7
There is no repository that provides ring 0.7
Error message:
error: no matching version `^0.7` found for package `ring`
location searched: registry `https://github.com/rust-lang/crates.io-index`
versions found: 0.12.1, 0.12.0, 0.11.0, ...
required by package `tfs-core v0.1.0 (file:///Users/liam/projects/redocs/tfs/core)`