Keycli mise env plugin

This is a little mise plugin to support keycli as a environment plugin

To use, you need to have a mise.toml like this:

[tools]
"cargo:keycli" = "latest"

[plugins]
keycli = "https://github.com/Headorteil/keycli-mise"

[env]
_.keycli = { tools = true, extra_args = "-e ENV_VAR:app/test" }